feat(search): local saved filter sets (saved searches)

[thomaschristory]

What

Adds LOCAL, named, persisted filter sets ("saved searches") per resource, mirroring the existing columns column-prefs pattern end to end.

A saved search is stored as the raw FilterState.as_params() dict (key=value), so it round-trips back through the TUI filter screen AND through parse_filters on the CLI. Kept framework-free and reusable by both surfaces.

Changes

• config: new Config.saved_searches: dict[tag][resource][name] = {filter_key: value} field; new framework-free nsc/config/saved_searches.py with get_saved_search / list_saved_searches.
• writer: _save_search / _delete_search round-trip persisters in tui_commands (set_path / unset_path under acquire_lock + atomic_write, pruning empty parents).
• TUI: FilterScreen gains Ctrl+W (save current state under a typed name) and Ctrl+O (load a saved set into the current FilterState + chips); new SavedSearchNamePrompt / SavedSearchPicker modals. NscTuiApp gains saved_searches_for / save_search / delete_search updating the in-memory map and calling write-through callbacks. tag/resource threaded into FilterScreen from ListScreen.
• CLI: --saved <name> global read flag on list ops. Resolves against config.saved_searches[tag][resource][name]; saved params are the base layer, explicit --filter and typed query options override them; unknown name → typer.BadParameter, exit 2.
• keymap/help/README: filter-context bindings added to the single-source-of-truth keymap; README documents the feature and its distinction from server-side extras saved-filters.

Precedence

Saved params merge UNDER explicit overrides: a typed query option or a --filter for the same key wins over the saved value.

Notes

• This is a LOCAL feature, deliberately distinct from NetBox's server-side /api/extras/saved-filters/ (different value format, per-user/instance, not available offline). Documented in --saved help text and README.
• Like columns, a config written by a newer nsc with saved_searches will not load on an older nsc (extra='forbid'). Consistent with existing behavior.
• FK filters persist as {name}_id=<id>; loading restores the id but not the human-readable FK label (chips show the id). Acceptable for v1.

Tests

TDD (red-first). New/updated tests:

• tests/config/test_models.py, tests/config/test_saved_searches.py
• tests/cli/test_tui_command.py (persist/delete), tests/cli/test_registration.py (resolve, override precedence, unknown-name exit 2)
• tests/tui/test_app.py, tests/tui/test_filter_screen.py (save callback, blank-name no-op, load repopulates), tests/tui/test_keymap.py

just lint (ruff + mypy --strict) and just test (1172 passed, 1 skipped) both green.

Closes #119

🤖 Generated with Claude Code

[thomaschristory]

Claiming: fixing the 3 code-review findings (dotted-name config corruption, missing TUI delete affordance, FilterScreen BINDINGS consistency) on branch feat/saved-searches. TDD, failing tests first.

[thomaschristory]

Pushed fixes (1eed396):

• BLOCKING (config corruption): added framework-free validate_saved_search_name (nsc/config/saved_searches.py) rejecting names with ., control chars, or surrounding whitespace. Enforced at entry (FilterScreen.action_save_search → error notification, no save) AND defensively in the _save_search persister before any disk write. Failing-first test proves a dotted name (prod.v2) no longer corrupts config.yaml.
• MAJOR (dead delete path): wired a delete affordance — d key binding in SavedSearchPicker dismisses with a typed SavedSearchChoice("delete", name) routed to the existing delete_search plumbing. Integration test covers it.
• MINOR (BINDINGS): skipped intentionally. FilterScreen is a ModalScreen that deliberately overrides global keys (escape→cancel, not go_back) and must NOT inherit globals like q→quit into a text-input form; deriving from textual_bindings('filter') would inject those and break typing — a real regression, which the finding said to skip.

lint + full suite green (1189 passed, 1 skipped).