Fix config, workspace, and project filter diagnostics

DEVELOPER_GUIDE.md

@@ -139,7 +139,7 @@ ownership boundaries so behavior changes remain reviewable and testable.
 
 ### Workspaces
 
-`cdidx.workspace.json` and `.cdidx-workspace.json` declare monorepo members without adding a YAML dependency. Workspace manifests are capped at 64 KiB, 16 JSON nesting levels, 1024 members, 4096 characters per member path, and 255 characters for `default_db_name`. The supported schema is additive: `members` is an array of member paths that must be relative to and resolve under the manifest directory, `index_strategy` is `per_member` or `single` with unknown values rejected, `default_db_name` is a plain file name that overrides `codeindex.db`, and `shared_ignores` is reserved for shared ignore policy. `cdidx workspace list` and `cdidx workspace status` report member DB paths.
+`cdidx.workspace.json` and `.cdidx-workspace.json` declare monorepo members without adding a YAML dependency. Workspace manifests are capped at 64 KiB, 16 JSON nesting levels, 1024 members, 4096 characters per member path, and 255 characters for `default_db_name`. The supported schema is additive: `members` is an array of member paths that must be relative to and resolve under the manifest directory, `index_strategy` is `per_member` or `single` with unknown values rejected, `default_db_name` is a plain file name that overrides `codeindex.db`, and `shared_ignores` is reserved for shared ignore policy. Invalid `members` entries are rejected with bounded diagnostics, and valid entries are normalized and deduplicated with the workspace path casing policy before DB paths are materialized. `cdidx workspace list` and `cdidx workspace status` report member DB paths.
 
 `cdidx workspace use <name>` writes an existing manifest member or `default` workspace to the per-user config directory, rejects missing manifest members, and rejects ambiguous member directory names. Query DB resolution keeps existing precedence: explicit `--db`, then explicit `--data-dir` / `CDIDX_DATA_DIR`, then active workspace state, then ancestor/CWD discovery.
 
@@ -216,7 +216,7 @@ Interactive terminal controls are allowed only when stdout is not redirected or
 
 `SolutionProjectResolver` parses the plain-text `.sln` `Project(...) = "...", "...csproj"` entries with a non-regex parser and resolves C# / F# / VB project files. Project entries that normalize outside the active workspace root are ignored before filesystem probing or path-filter evaluation. Solution parsing rejects `.sln` files above 8 MiB, lines above 16,384 characters, and more than 4096 .NET project references with clear diagnostics. Automatic root-level `.sln` discovery samples at most 128 candidates before sorting and reports a clear error when that cap is exceeded, so callers should pass `--solution <path>` in solution-heavy workspaces. When exactly one `.sln` exists at the workspace root within that cap, `--project <name|path>` uses it automatically; otherwise callers can pass `--solution <path>`. Fallback project discovery caps traversal at 4096 directories and 65,536 files with a clear `--solution <path>` recovery hint. Fallback project discovery and project-file expansion use long-path-safe per-directory enumeration, skip unreadable subtrees, and include bounded traversal diagnostics when a project filter cannot be resolved.
 
-Query commands that accept path filters (`search`, `definition`, `references`, `callers`, `callees`, `symbols`, `files`, `find`, `map`, `inspect`, `deps`, `impact`, `unused`, `hotspots`, and `validate`) expand `--project` into the matching project directory glob before hitting `DbReader`, so all existing SQL path predicates keep working. `index --project` expands to the files under the selected project directory and reuses the existing `--files` update path, but rejects expansions above 65,536 files for one project or 131,072 unique files across all requested projects with an explicit-files recovery hint.
+Query commands that accept path filters (`search`, `definition`, `references`, `callers`, `callees`, `symbols`, `files`, `find`, `map`, `inspect`, `deps`, `impact`, `unused`, `hotspots`, and `validate`) expand `--project` into the matching project directory glob before hitting `DbReader`, so all existing SQL path predicates keep working. When the indexed project root cannot be resolved and project expansion falls back to the process current directory, CLI query context and MCP structured payloads include `project_filter_root` and `project_filter_root_fallback_reason`. `index --project` expands to the files under the selected project directory and reuses the existing `--files` update path, but rejects expansions above 65,536 files for one project or 131,072 unique files across all requested projects with an explicit-files recovery hint.
 
 `cdidx batch` is a CLI-side query loop for editor integrations and scripts that need several query commands against the same DB without spawning `cdidx` repeatedly. It opens one `DbContext` / `DbReader`, reads newline-delimited JSON string arrays from stdin, caps each decoded string argument at 8,192 characters, and dispatches only query commands through the existing `QueryCommandRunner` paths so output and validation stay identical to the standalone command shape.
 
@@ -2249,11 +2249,14 @@ ownership boundary を分けるときは、挙動変更を review しやすく t
 ### ワークスペース
 
 `cdidx.workspace.json` と `.cdidx-workspace.json` は YAML dependency を増やさずに monorepo
-member を宣言します。workspace manifest は 64 KiB、JSON nesting 16 level、1024 members に制限されます。
+member を宣言します。workspace manifest は 64 KiB、JSON nesting 16 level、1024 members、
+member path 4096 characters、`default_db_name` 255 characters に制限されます。
 schema は additive で、`members` は manifest directory からの相対 path かつ正規化後も
 manifest directory 配下に残る member path、
 `index_strategy` は `per_member` または `single`、`default_db_name` は
 `codeindex.db` を上書きする plain file name、`shared_ignores` は共有 ignore policy 用の予約 field です。
+invalid な `members` entries は件数を制限した diagnostics で拒否され、有効な entry は DB path を
+作る前に workspace path casing policy で正規化・重複排除されます。
 `cdidx workspace list` と `cdidx workspace status` は member DB path を報告します。
 
 `cdidx workspace use <name>` は active workspace を per-user config directory に保存します。
@@ -2360,7 +2363,7 @@ override が文書化されていない限り ANSI/progress control を抑止す
 
 `SolutionProjectResolver` は plain-text の `.sln` に含まれる `Project(...) = "...", "...csproj"` 行を non-regex parser で読み、C# / F# / VB の project file を解決する。active workspace root の外側へ正規化される project entry は、filesystem probe や path-filter 評価の前に無視する。solution parsing は 8 MiB を超える `.sln`、16,384 文字を超える行、4096 件を超える .NET project reference を明確な diagnostic とともに拒否する。root 直下の `.sln` 自動検出は sort 前に最大 128 candidates で打ち切り、その上限を超えた場合は明確な error を返すため、solution が多い workspace では `--solution <path>` を渡す。上限内で workspace root に `.sln` が 1 つだけある場合、`--project <name|path>` は自動でそれを使う。複数ある場合は caller が `--solution <path>` を渡せる。fallback project discovery は 4096 directories / 65,536 files で traversal を打ち切り、`--solution <path>` を示す明確な recovery hint を返す。fallback project discovery と project-file expansion は long-path-safe な per-directory 列挙を使い、読めない subtree を skip し、project filter を解決できない場合は bounded traversal diagnostics を含める。
 
-path filter を受け付ける query コマンド（`search`, `definition`, `references`, `callers`, `callees`, `symbols`, `files`, `find`, `map`, `inspect`, `deps`, `impact`, `unused`, `hotspots`, `validate`）は、`--project` を対応する project directory glob に展開してから `DbReader` に渡す。これにより既存の SQL path predicate をそのまま利用できる。`index --project` は選択された project directory 配下のファイルに展開し、既存の `--files` 更新経路を再利用する。ただし 1 project で 65,536 files、requested projects 全体で 131,072 unique files を超える展開は拒否し、明示的な `--files` を使う recovery hint を返す。
+path filter を受け付ける query コマンド（`search`, `definition`, `references`, `callers`, `callees`, `symbols`, `files`, `find`, `map`, `inspect`, `deps`, `impact`, `unused`, `hotspots`, `validate`）は、`--project` を対応する project directory glob に展開してから `DbReader` に渡す。これにより既存の SQL path predicate をそのまま利用できる。indexed project root を解決できず process current directory に fallback して project expansion する場合、CLI query context と MCP structured payload は `project_filter_root` と `project_filter_root_fallback_reason` を含める。`index --project` は選択された project directory 配下のファイルに展開し、既存の `--files` 更新経路を再利用する。ただし 1 project で 65,536 files、requested projects 全体で 131,072 unique files を超える展開は拒否し、明示的な `--files` を使う recovery hint を返す。
 
 `cdidx batch` は、同じ DB に複数の query command を投げる editor integration や script 向けの CLI 側 query loop である。1 つの `DbContext` / `DbReader` を開き、stdin から newline-delimited JSON 文字列配列を読み、デコード後の各文字列引数を 8,192 文字に制限し、query command だけを既存の `QueryCommandRunner` 経路へ dispatch するため、出力と validation は単発コマンドと同じ形を保つ。