Remove internal-only tooling from the external build (#352)

* Remove internal-only tooling without changing external runtime contracts

This trims the lowest-risk internal-only surfaces first: deleted internal
modules are replaced by build-time no-op stubs, the bundled stuck skill is
removed, and the insights S3 upload path now stays local-only. The privacy
verifier is expanded and the remaining bundled internal Slack/Artifactory
strings are neutralized without broad repo-wide renames.

Constraint: Keep the first PR deletion-heavy and avoid mass rewrites of USER_TYPE, tengu, or claude_code identifiers
Rejected: One-shot DMCA cleanup branch | too much semantic risk for a first PR
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Treat full-repo typecheck as a baseline issue on this upstream snapshot; do not claim this commit introduced the existing non-Phase-A errors without isolating them first
Tested: bun run build
Tested: bun run smoke
Tested: bun run verify:privacy
Not-tested: Full repo typecheck (currently fails on widespread pre-existing upstream errors outside this change set)

* Keep minimal source shims so CI can import Phase A cleanup paths

The first PR removed internal-only source files entirely, but CI provider
and context tests import those modules directly from source rather than
through the build-time no-telemetry stubs. This restores tiny no-op source
shims so tests and local source imports resolve while preserving the same
external runtime behavior.

Constraint: GitHub Actions runs source-level tests in addition to bundled build/privacy checks
Rejected: Revert the entire deletion pass | unnecessary once the import contract is satisfied by small shims
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: For later cleanup phases, treat build-time stubs and source-test imports as separate compatibility surfaces
Tested: bun run build
Tested: bun run smoke
Tested: bun run verify:privacy
Tested: bun run test:provider
Tested: bun run test:provider-recommendation
Not-tested: Full repo typecheck (still noisy on this upstream snapshot)

---------

Co-authored-by: anandh8x <test@example.com>

src/constants/prompts.ts

@@ -242,7 +242,7 @@ function getSimpleDoingTasksSection(): string {
       : []),
     ...(process.env.USER_TYPE === 'ant'
       ? [
-          `If the user reports a bug, slowness, or unexpected behavior with Claude Code itself (as opposed to asking you to fix their own code), recommend the appropriate slash command: /issue for model-related problems (odd outputs, wrong tool choices, hallucinations, refusals), or /share to upload the full session transcript for product bugs, crashes, slowness, or general issues. Only recommend these when the user is describing a problem with Claude Code. After /share produces a ccshare link, if you have a Slack MCP tool available, offer to post the link to #claude-code-feedback (channel ID C07VBSHV7EV) for the user.`,
+          `If the user reports a bug, slowness, or unexpected behavior with Claude Code itself (as opposed to asking you to fix their own code), recommend the appropriate slash command: /issue for model-related problems (odd outputs, wrong tool choices, hallucinations, refusals), or /share to upload the full session transcript for product bugs, crashes, slowness, or general issues. Only recommend these when the user is describing a problem with Claude Code.`,
         ]
       : []),
     `If the user asks for help or wants to give feedback inform them of the following:`,