AGENTS.md: dedupe the section 2 state tree into its declared owners

[jbassiri]

Motivation

AGENTS.md is loaded in full by every firstmate session (CLAUDE.md is a symlink to it), so its byte size is a fixed token cost paid at every session start. This PR removes the one remaining block that duplicates content the repo already assigns to other owners, reducing that always-loaded cost without touching any rule.

What changed

Section 2 ("Layout and state") still inlined an exhaustive state/ + config/ file tree that restates exact child-file fields, even though the repo already assigns that content elsewhere:

• Section 2's own opening line names docs/configuration.md as "the single owner of the operational-home layout, configuration schemas, and reference state map", and each producing script's header/--help as the owner of exact child fields and mutation mechanics.
• docs/configuration.md ("Operational home layout and state") assigns child fields to producer script headers and deliberately keeps wake/watcher/away-mode/X state "rather than being duplicated into one exhaustive state tree here".

So the inline tree was the last remaining duplicate of content the one-owner rule (per firstmate-coding-guidelines) assigns to docs/ and script headers. It is replaced with a concise pointer to those owners. Preserved inline: the two boundaries that bind at every turn (projects/ is read-only; state/ watcher/sub-supervisor/wake internals are never hand-edited) and the CLAUDE.md / .claude/skills symlink facts.

Size

	bytes
AGENTS.md before	44,901
AGENTS.md after	38,023

A 6,878-byte (~15%) reduction in the always-loaded surface.

Not a rewrite

This is a pure dedupe of reference detail; no safety boundary, prime directive, or ownership pointer was weakened, dropped, or reworded. The two load-bearing section-2 facts that were interleaved in the tree (state/<id>.status is a wake event; data/captain.md/data/learnings.md canonicity) are untouched. The sections the repo marks as always-loaded operational contracts (task lifecycle, supervision) are left exactly as-is.

Validation

bin/fm-lint.sh passes (shellcheck 0.11.0). The instruction-ownership and cross-reference tests pass, including fm-instruction-owners (which asserts the section-2 owner pointer, the always-loaded contracts, and the retained safety phrases), fm-no-mistakes-ownership, fm-stow-contract, and fm-ensure-agents-md. No test asserts the removed tree's contents. The CLAUDE.md -> AGENTS.md and .claude/skills -> ../.agents/skills symlinks are untouched.