ci(release): install web dependencies before build

[tickernelz]

Problem

The v2.22.0 release run failed during bun run build because the release workflow installed only root dependencies. Since #201, the root build invokes the web TypeScript/Vite build, which requires web/node_modules.

Failed run: https://github.com/tickernelz/opencode-mem/actions/runs/30507159676

Fix

• install root dependencies with bun install --frozen-lockfile
• install web dependencies from web/bun.lock before typecheck/build

Verification

Reproduced the exact release install/typecheck/build sequence in a clean detached worktree with neither root nor web node_modules present:

• root frozen install: pass
• web frozen install: pass
• bun run typecheck: pass
• bun run build: pass
• dist/plugin.js: present
• dist/web/index.html: present

[tickernelz]

Confirmed in production release v2.22.0: the corrected workflow installed both dependency sets, built the package and React UI, published to npm, and created the GitHub Release successfully.

Run: https://github.com/tickernelz/opencode-mem/actions/runs/30507456715