Update final candidate status

[suraciii]

What Changed and Why

Update the release status in ROADMAP, product documentation, technical design,
compatibility guidance, and the fuzz-budget research record. The fixed-budget
candidate now has exact local and hosted proof. The exact tagged-module proof
and the release boundary remain open.

This removes stale status after PR #119 without changing product behavior.

Related Issue

Related to #109. This pull request does not close it because the exact
v0.1.0 tagged-module proof is still required.

Specification

This updates Batch 8e in design/release-0.1.0.md and the matching status in
ROADMAP.md. The implementation still matches the specification. The Gap
sections now describe only the remaining tagged-module and release boundary.

Breaking Changes and Migration

None.

User-Visible Change

NONE

Verification

Exact commit: 8a864c7ef5a07de0323c894fb10917862db4d61a

• git diff --check: passed.
• go run ./internal/constraintcheck: passed.
• make external after go clean -testcache: passed with exit 0 in 63.58
  seconds. It started 4 release-command contract tests, 1 Quick Start test,
  and 20 conformance tests, including the exact v0.0.5 upgrade.
• make ci after go clean -testcache: passed with exit 0 in 50.71 seconds.
  It started 4 release-command contract tests, 639 default tests, 20
  simulation tests, 19 generator tests, 45 Transport network tests, 50 Shadow
  network tests, the two resource-bound tests, and all three fixed fuzz runs.
• Independent review found no P0 issue and confirmed that the stale
  compatibility status was corrected. The new squash commit still requires
  exact local and hosted proof before release.

Mutation Test

N/A. This is a documentation-only change.

Required Checks

• make ci passes locally.
• Old and new tests do not test the same contract. No tests changed.
• Production code does not call time.Now(). No production code changed.
• Tests do not use time.Sleep for synchronization. No tests changed.
• Code does not use a mutex to wait across Calls. No code changed.
• A specification supports the change. It states each implementation gap.

[suraciii]

Exact pull request head 8a864c7ef5a07de0323c894fb10917862db4d61a
passed hosted run
31506609883:

• Go 1.25.12 passed in 4 minutes 8 seconds;
• stable Go 1.26.5 passed in 3 minutes 53 seconds, and govulncheck
  reported no known vulnerabilities;
• macOS passed in 55 seconds;
• Windows passed in 2 minutes 6 seconds; and
• aggregate CI passed in 3 seconds.

Both Linux jobs started the required test lanes and completed exactly
1,600,000, 225,000, and 2,250,000 fuzz executions.

The squash commit will be a new candidate SHA. Before release, that exact
master commit still requires a fresh local make external, local make ci,
and hosted supported-system run. Issue #109 remains open for that proof and the
exact tagged-module boundary.

[suraciii]

Post-merge proof is complete on exact master commit
6e692d587f8a6f1556a5c8539febdce4ad9f13f6 (tree
5c8b8aa7a1ecd7954f4a8a55edcdc5b493b35068).

• The detached proof worktree was clean and matched origin/master.
• make external after go clean -testcache: exit 0 in 64.14 seconds. It
  started 4 release-command contract tests, 1 Quick Start test, and 20
  conformance tests, including restart recovery and the exact v0.0.5
  upgrade.
• make ci after go clean -testcache: exit 0 in 56.60 seconds. It started
  all required nonzero test lanes and completed the two resource checks and
  all fixed fuzz budgets.
• Exact-master hosted run
  31507196601
  passed Go 1.25.12, stable Go 1.26.5 with no known vulnerabilities, macOS,
  Windows, and aggregate CI.
• Both Linux jobs completed exactly 1,600,000, 225,000, and 2,250,000 fuzz
  executions.

The final same-commit candidate proof is complete. Issue #109 remains open for
maintainer authorization, the exact v0.1.0 tag, successful
make external-tagged, and the GitHub Release.