ci: add Bump Version workflow for automated release prep

[SavioBS629]

What

Adds a workflow_dispatch workflow (Bump Version) that bumps the package version across all three version-bearing files and opens a PR titled chore: bump version to <X.Y.Z>.

This automates the manual three-file version bump that must precede the Release New Version workflow (per the release flow in the contributor docs).

Files bumped by the workflow

File	Field
package.json	top-level version
package-lock.json	top-level version + packages[""].version (via npm version)
server.json	packages[0].version only — the top-level 1.0.0 schema version is left untouched

After the bump PR merges, trigger Release New Version to tag + publish.

Inputs

• version — explicit target (e.g. 1.2.23), or
• bump — patch / minor / major increment (used when version is blank)

Safety

• workflow_dispatch-only (write access required to trigger)
• All inputs validated (semver / enum) and passed via env: — no shell interpolation of user input
• Scoped permissions: (contents: write, pull-requests: write); uses the auto-provided GITHUB_TOKEN
• A sync-check step fails the run if the four version fields don't all match before committing

Verification

Validated end-to-end on a scratch repo mirroring this structure — produces exactly the 3-file diff shape (e.g. PR #326), with server.json's schema version untouched.

🤖 Generated with Claude Code