chore(release): cut v1.8.27

[KbWen]

Summary

Cuts v1.8.27. It packages the units merged since v1.8.26:

• fix(deploy): ignore Python bytecode downstream #435 (closes Deployed .gitignore omits __pycache__/ and *.pyc, so the framework's own tools dirty the adopter's tree #430): the deployed .gitignore block ignores the framework's own bytecode, scoped to .agentcortex/**/__pycache__/. Re-deploys stay byte-identical.
• docs(skills): lead two skill descriptions with their activation conditions #437 / docs(retro): move the #437 learnings from private memory into repo records #438: two skill descriptions now lead with their activation conditions, plus that unit's retro records.
• chore(deps): bump trufflesecurity/trufflehog from 3.96.0 to 3.97.1 #425: the TruffleHog scanner digest now matches the wrapper release.
• docs: point the custom-* skills row at its activation on-ramp #436: the custom-* activation on-ramp row in docs/INSTALL.md.

What this PR changes:

• the seven version surfaces plus CITATION.cff date-released
• the CHANGELOG entry
• the Ship History entry, with cap-10 rotation
• the heartbeat, now 172
• the archived Work Log

The cut itself changes no engine, gate, deployed file set, or configuration.

Adopter delta: 6 of the 26 files changed since v1.8.26 are in the deploy set. The notes lead with the one adopter action: git rm -r --cached .agentcortex/tools/__pycache__, for installs that already committed bytecode.

Classification

• quick-win (release cut, chore/release-v1.8.26 precedent)

Evidence

• test_release_version_consistency.py: 2 passed
• validate.sh / validate.ps1: exit 0, pass=99 warn=4 fail=0 skip=3, identical (all 4 warnings were already present)
• Audit chain intact; SSoT caps 10/10
• Whole suite: runs on this PR's CI. The unchanged code had a local 951-test run plus green CI on fix(deploy): ignore Python bytecode downstream #435.

Not done at merge

The release is not finished when this merges. Two manual steps remain (repo-gotchas §12):

1. Lightweight tag v1.8.27 on the merge commit, then push it.
2. gh release create v1.8.27 --latest

🤖 Generated with Claude Code