Add opt-in decision providers, improve retrieval performance, and support Pi 1.2

[RodCor]

Pi 1.2 custom turns can lack a prompt, repeated revision queries reparse the same SQL, and file capsule expansion reads an entire file to return only 2048 bytes. This change synchronizes the fixed Pi extension, caches revision queries, and bounds capsule reads. It also adds an experimental, explicitly requested brain context decision pass for TypeSafe Jev, OpenAI Decisions and Perplexity Decisions; defaults and automatic host integrations stay unchanged.

Provider configuration alone makes no request. Both --decisions and an explicit probability threshold are required. The pass preserves local abstention, validates every response before mutation, filters only already-selected evidence, and uses bounded transport with no redirects/retries/fallback. No hosted service was called; contract and HTTP mock tests do not establish access, quality or calibration.

Release metadata is prepared and verified for 2.9.0: all seven workspace crates and lockfile entries, all 13 inter-crate version pins, and the changelog agree. npm CLI/server manifests intentionally remain 0.0.0 templates because release.yml stamps them from the release tag; the SDK retains its independent version. Merging alone does not publish. After genuine required approval, merge, and verification of the merged commit, create v2.9.0 at that exact merged SHA and push that tag. The tag triggers release.yml, which validates tag/version agreement, builds and smoke-tests artifacts, publishes the GitHub release, and runs enabled crates.io/npm publication jobs. PUBLISH_CRATES and PUBLISH_NPM are currently true; publishing still requires the existing workflow credentials. No pre-merge tag or publication is authorized by this preparation step.

Validation and evidence:

• Pi package PR release: v0.8.3 — fix Windows npm package #13 in RodCor/kimetsu-pi: 36 tests, real Pi 1.2 runtime and Kimetsu 2.8.0 CLI; independent review and cross-platform CI; plugin 0.1.5 published.
• Core baseline: 740 brain tests and two doctests. New tests cover UTF-8/byte boundaries, provider contracts and actual loopback HTTP, opt-in CLI/configuration, abstention and filter invariants. Python tests include malformed-key error sanitization.
• Release benchmark: 1000 memories/10 revisions, 15 batches of 100 operations per side. Median recency retrieval time decreased 44.6%; 32-MiB file expansion 99.4%. Selected evidence fingerprints and returned file bytes match. Small lexical differences are not a quality claim.
• Three fresh paired offline research retests found no strict gain; no research patch was adopted.
• Durable methodology, raw batches, research results and limitations: docs/audits/2026-10-13-review/README.md.
• Independent code review approved the previous PR head 3dc7808b020b471ac50cc28d1adce335ea280100; all CI jobs passed except the dependency audit, including Windows/macOS/Linux, explicit embeddings, both lint builds, CodeQL, SDK, formatting, examples and asset drift.
• CI's dependency audit found six pre-existing advisories affecting locked quinn-proto 0.11.15 and rustls 0.23.40. An independently reviewed follow-up commit eef1a018596f6757f30e3f41cdd926bb1a3b1ee0 updates to patched 0.11.18 and 0.23.45 plus required transitive dependencies. Its full local workspace suite passed 1439 tests (five pre-existing ignores), Python passed eight, and Pi passed 36 including real CLI integration against the 2.9.0 candidate. Local audit reports zero vulnerabilities with the existing informational exceptions only.
• The user explicitly authorized the ordinary push of the tested dependency fix after being informed of the automatic owner bypass. Remote head is now eef1a01. GitHub again reported an automatic branch-update bypass; no force push, protection changes, or admin merge was requested. All 17 checks passed on this exact head: CI https://github.com/RodCor/kimetsu/actions/runs/38423066226 and both CodeQL runs https://github.com/RodCor/kimetsu/actions/runs/38423063096 and https://github.com/RodCor/kimetsu/actions/runs/38423063489. GitHub audit reports zero vulnerabilities.
• This PR is marked ready. Merge and release remain gated on all applicable CI checks and genuine GitHub code-owner/latest-push approval; independent agent review does not replace that approval. No core release has been tagged or published.