chore(skills): canonical sync — warm-start, objectives (ECO family), problem-types (density routing) from the staging copies

[aarontrowbridge]

The #474 landing queued a canonical-sync PR that was never filed; the 2026-09-05 trajectory-coverage campaign landed two more machinery changes with their knowledge passes applied to the STAGING copies only (live for sessions, but the amicode-repo canonical copies are now behind):

1. warm-start (from BUG: .docx files rejected by file picker and at upload — format not supported #474, 2026-09-03): the infeasible state warm-start seed-source class, the set_state_guess! mechanics section, the three honesty rules — already in staging, never synced.
2. objectives (from docs(m2): app-extraction inventory + manifest stamps (M4 complete) #480, 2026-09-05): the ECO family section — ChannelProcessInfidelityObjective (dual-basis representation, the W-metric invariant, the |1−F_pro| envelope, F_pro ≠ F_avg, rollout-FD-only gradient checks), the PauliWeightSpectrumPenalty shape (ECO-2, in flight), the A1 sauce boundary.
3. problem-types (from BUG: Input box loses focus and turns yellow when background diagnostics collection completes mid-typing #478, 2026-09-05): Density/MultiDensity matrix-free routing (Piccolissimo ≥ 94fcac3, routed 4.2× vs dense), MultiDensity row (channel substrate), the bang-bang plateau caveat.

Staging copies (source of truth for this sync): /home/aaron/.amico/server/opencode-project-staging/opencode-project/skills/{warm-start,objectives,problem-types}/SKILL.md.

Slice: one PR, copy-verify the three files against staging, run the skills fixture/healthcheck if present, cite the landing PRs (#474/#480/#478) in the diff descriptions. Low-risk chore tier — no design phase.

[aarontrowbridge]

Mis-targeted on filing: the canonical home for the physics skills (warm-start/objectives/problem-types) is harmoniqs/armonissima, not this repo — the sync is tracked as armonissima #84 + PR (branch chore/84-skills-canonical-sync). Closing here with the pointer.