feat: dbt_defer_state tool — Power User defer setting and profile target - #1734

Type of change

• New feature

What does this PR do?

Implements the dbt_defer_state tool (package P-04, altimate-code half). Given a dbt project folder it reads dbt.deferConfigPerProject from .vscode/settings.json (comments and trailing commas allowed), finds the entry keyed by the project's path relative to its workspace folder, and returns { enabled, favorState, mode, stateDir, reason, defaultTarget, targets }.

• Local mode: manifestPathForDeferral (with ${workspaceFolder} and ${env:NAME} expanded, relative paths resolved against the project) is returned as stateDir only when it is a directory; otherwise reason says why.
• Remote mode: reported as mode: remote with enabled: false and a clear reason. The request shape of dbt/v1/fetch_artifact_url could not be verified, so no download is attempted and api/fetch-artifact-url.ts is not added.
• The profile's default target and its output names come from profiles.yml (DBT_PROFILES_DIR, the project folder, then ~/.dbt).
• Read-only.

This branch includes the foundation commits (dbt Power User tool foundation); retarget/rebase once that PR merges. The plugin half is in the altimate-claude-plugin PR for feat/defer-target, which should merge after this one.

How did you verify your code works?

• bun test test/altimate/dbt-defer-state.test.ts: 8 tests pass (local mode, defer off, no entry, root project key, non-directory state path, remote reported unsupported, missing settings/profiles, comments and trailing commas).
• bun typecheck passes.

Cost side effects

None. The tool only reads local files; it adds no model calls, warehouse queries or cloud resources.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR
• I checked for cost side effects (model calls, queries or cloud resources that grow with user data) and described them, or wrote "none"

Changelog

• Added dbt_defer_state: reads the dbt Power User defer-to-production setting and the profile's default target for a dbt project.

🤖 Generated with Claude Code

Summary by cubic

Adds the dbt_defer_state tool, which reads the dbt Power User defer setting from .vscode/settings.json and reports whether defer is on, the state directory, and the profile's default target, plus the foundation the other dbt Power User tools build on.

• Local mode returns the configured state directory even while defer is off, so a session can switch it on; the directory must hold a manifest.json. Remote mode, missing or unparseable settings, unknown manifest types, and non-directory paths are reported with reasons instead; env_var() in the profile, target, and state path is resolved.
• Adds dbtAdapterFor, the gate every adapter-backed tool goes through: it refuses read-only calls, plan mode, sessions in other projects, and adapters that failed to start.
• Adds AltimateApi.apiRequest for endpoint files to call the backend with the stored credentials.
• Exposes nine dbt tool stubs; the eight beyond dbt_defer_state return "not implemented" placeholders.
• dbt_defer_state is read-only; it adds no API calls, warehouse queries, or cloud resources.

^{Written for commit 983309a. Summary will update on new commits.}