fix(installer): opencode .jsonc + AGENTS.md (0.7.8) (#163)

* release: 0.7.7 (multi-agent installer — Cursor, Codex, opencode)

* fix(installer): opencode .jsonc + AGENTS.md (0.7.8)

v0.7.7 wrote ~/.config/opencode/opencode.json, but opencode reads
opencode.jsonc by default — so the codegraph MCP entry never appeared
in any opencode session. Also installs AGENTS.md so opencode's model
reaches for codegraph_* tools instead of native Grep.

- Prefer existing .jsonc, fall back to .json, default new installs
  to .jsonc.
- Surgical edits via jsonc-parser preserve user comments and
  formatting across install / re-install / uninstall round-trips.
- Install AGENTS.md (global ~/.config/opencode/AGENTS.md, local
  ./AGENTS.md) with the shared INSTRUCTIONS_TEMPLATE — same
  marker-delimited approach Codex uses.
- +9 opencode-specific tests covering filename precedence, comment
  preservation, AGENTS.md install + sibling-content preservation,
  uninstall reverses both files.

575/575 tests pass. Hand-verified end-to-end: opencode session calls
codegraph_node + codegraph_callers for a structural query, zero Grep
calls.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: overhaul CLAUDE.md and add scripts/release.sh + Cursor rules file

Replaces the old Claude-only CLAUDE.md with a comprehensive guide covering
the full project architecture, multi-agent installer, test conventions,
NodeKind/EdgeKind reference, and release workflow. Key additions:

- Documents the layered pipeline, all module paths, and the multi-target
  installer (targets/, registry.ts, AgentTarget interface).
- Adds the Cursor `--path` quirk and the "update all three surfaces" rule
  when changing MCP tool guidance.
- Documents `npm run eval`, `test:eval`, and the full set of build/test
  commands including single-file patterns.
- `scripts/release.sh` — idempotent bash script that tags the current
  commit, pushes the tag, and creates a GitHub Release whose notes are
  extracted from the matching `## [X.Y.Z]` block in CHANGELOG.md. Safe
  to re-run after partial failure.
- `.cursor/rules/codegraph.mdc` — Cursor-specific agent instructions
  (tool decision table, rules of thumb, index-lag warning) written by
  the installer and kept in sync with server-instructions.ts and
  instructions-template.ts.

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/release.sh

@@ -0,0 +1,70 @@
+#!/usr/bin/env bash
+# Tag the current commit with the version in package.json and publish a
+# matching GitHub Release whose body is the corresponding CHANGELOG.md entry.
+#
+# Run AFTER you have:
+#   - bumped package.json
+#   - added a `## [X.Y.Z] - YYYY-MM-DD` block at the top of CHANGELOG.md
+#   - committed, pushed to origin, and run `npm publish`
+#
+# Idempotent: safe to re-run after a partial failure. Skips steps that are
+# already done (tag created, tag pushed, release published).
+#
+# Usage: ./scripts/release.sh
+
+set -euo pipefail
+
+cd "$(dirname "$0")/.."
+
+VERSION=$(node -p "require('./package.json').version")
+TAG="v${VERSION}"
+
+REPO=$(git remote get-url origin | sed -E 's|.*github\.com[:/]||; s|\.git$||')
+if [ -z "${REPO}" ]; then
+  echo "error: could not derive owner/repo from origin remote URL" >&2
+  exit 1
+fi
+
+if ! grep -q "^## \[${VERSION}\]" CHANGELOG.md; then
+  echo "error: no '## [${VERSION}]' entry found in CHANGELOG.md" >&2
+  exit 1
+fi
+
+NOTES=$(awk -v v="${VERSION}" '
+  /^## \[/ {
+    if (p) exit
+    if ($0 ~ "^## \\[" v "\\]") p = 1
+  }
+  p
+' CHANGELOG.md)
+
+if [ -z "${NOTES}" ]; then
+  echo "error: failed to extract changelog notes for ${VERSION}" >&2
+  exit 1
+fi
+
+if git rev-parse "${TAG}" >/dev/null 2>&1; then
+  echo "✓ tag ${TAG} already exists locally"
+else
+  echo "→ tagging ${TAG}"
+  git tag "${TAG}"
+fi
+
+if git ls-remote --exit-code --tags origin "${TAG}" >/dev/null 2>&1; then
+  echo "✓ tag ${TAG} already on origin"
+else
+  echo "→ pushing ${TAG} to origin"
+  git push origin "${TAG}"
+fi
+
+if gh release view "${TAG}" --repo "${REPO}" >/dev/null 2>&1; then
+  echo "✓ release ${TAG} already published"
+else
+  echo "→ creating GitHub Release ${TAG} on ${REPO}"
+  gh release create "${TAG}" \
+    --repo "${REPO}" \
+    --title "${TAG}" \
+    --notes "${NOTES}"
+fi
+
+echo "done: https://github.com/${REPO}/releases/tag/${TAG}"