[@corbits/google-tools] publish-prep: publishConfig + exports

[TheGreatAxios]

Publish prep for @corbits/google-tools (no version change, no bundler added).

• Add "publishConfig": { "access": "public" } so scoped package publishes publicly.
• Rename exports condition key "bun" -> "intx-src" on both subpaths (., ./sidecar-bundle), preserving order { intx-src, types, default } and ./src/*.ts targets.
• Confirmed files already includes dist + LICENSE + README; sideEffects already present. No other changes.

Verification:

• bun install: exit 0
• bun run build: exit 0
• npm pack --dry-run: succeeds (63 files, includes dist + LICENSE + README)
• Node smoke: self-reference import resolves to dist/index.js (not src); dist import ok.

Fixes CL-8954