docs(release): record the v0.5.0 tag and release (plan r12, part 8) - #22

Summary

V0.5 is out. This PR writes the result in the three documents that said "after the release".

docs/PLAN/PLAN-RUST-AGENT-RUNTIME-REMOVAL.md
  header, "Current state", "What it is"   v0.5.0 is released (tag on be3f8a8)
  exit condition 1                        CI on be3f8a8; TUI CI counted from 9058ab3 (same tui/ tree)
  exit condition 2                        shipped sizes: Linux 420,720,608 B, macOS 49,272,472 B
  exit condition 3, 5                     the tag-push side of the `if` ran; release body = CHANGELOG section
  exit condition 6                        tag, Release run (3 attempts), PyPI, GitHub Release, shipped Linux binary
  "Not verified": release build           Linux binary run; macOS binary never started
  "Next steps"                            "check again before the tag" removed; release.yml `repo-token` added (needs the owner)
docs/PLAN/archive/...-EXECUTION-LOG.md    part 8: merge of #20 and #21, tag, Release run, checks of the result
docs/baselines/tui.md                     sizes of the two shipped binaries

Evidence

• Before: The plan said "the CI on the tag commit is recorded after the release", "check once more before the tag" and "the result is added after the release". The list "not verified" said that nobody ran a release build.
  After: Each of these has its result, with run links. The key numbers come from sources that I read again for this PR:
  • Release run 38358144687: job times of the three attempts from the Actions API; the failed step is "Install protoc" (18 s and 22 s).
  • GitHub Release: 14 assets, releases/latest is v0.5.0, the body is equal to the awk output of the tagged CHANGELOG.md (49,639 B).
  • Shipped Linux binary, run in WSL2 with the agent from PyPI: smoke.py 23/23, --sandbox workspace 26/26, status_line_probe.py 4/4, resume_matrix.py 11 pass / 2 GAP / 0 fail, exit_matrix.py 12/12.
• git diff 1fa18cf be3f8a8 -- tui packages pi_agent_core pyproject.toml scripts .github is empty: the trees that CI and the dry run tested are the trees that shipped.
• ruff check . and ruff format --check . pass. Only text changes.
• Not verified: the macOS binary (nobody started it); a Windows binary does not exist; I did not run the local pytest or cargo tests (the owner said they are not needed). Two size differences are recorded and not explained: the shipped Linux binary is 53,408 B larger than the release_baseline number, and the macOS binary is much smaller than the Linux one.

Merge Danger

Door: two-way

Only text changes. A revert puts the old text back. The tag v0.5.0 stays on be3f8a8; this PR does not move it.

Blast Radius: project notes

Plan, execution log and baselines. TUI CI does not start for this PR (its path filter has no document path); CI does. The plan now lists one open item for the owner: add repo-token to the two setup-protoc steps in release.yml (the missing token failed the macOS build twice in the Release run).