Reduce internal-only labeling noise in source comments (#355)

This pass rewrites comment-only ANT-ONLY markers to neutral internal-only
language across the source tree without changing runtime strings, flags,
commands, or protocol identifiers. The goal is to lower obvious internal
prose leakage while keeping the diff mechanically safe and easy to review.

Constraint: Phase B is limited to comments/prose only; runtime strings and user-facing labels remain deferred
Rejected: Broad search-and-replace across strings and command descriptions | too risky for a prose-only pass
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Remaining ANT-ONLY hits are mostly runtime/user-facing strings and should be handled separately from comment cleanup
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 (upstream baseline remains noisy)

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

src/constants/prompts.ts

@@ -1,4 +1,4 @@
-// biome-ignore-all assist/source/organizeImports: ANT-ONLY import markers must not be reordered
+// biome-ignore-all assist/source/organizeImports: internal-only import markers must not be reordered
 import { type as osType, version as osVersion, release as osRelease } from 'os'
 import { env } from '../utils/env.js'
 import { getIsGit } from '../utils/git.js'
@@ -389,7 +389,7 @@ function getSessionSpecificGuidanceSection(
       : null,
     hasAgentTool &&
     feature('VERIFICATION_AGENT') &&
-    // 3P default: false — verification agent is ant-only A/B
+    // 3P default: false — verification agent is internal-only A/B
     getFeatureValue_CACHED_MAY_BE_STALE('tengu_hive_evidence', false)
       ? `The contract: when non-trivial implementation happens on your turn, independent adversarial verification must happen before you report completion \u2014 regardless of who did the implementing (you directly, a fork you spawned, or a subagent). You are the one reporting to the user; you own the gate. Non-trivial means: 3+ file edits, backend/API changes, or infrastructure changes. Spawn the ${AGENT_TOOL_NAME} tool with subagent_type="${VERIFICATION_AGENT_TYPE}". Your own checks, caveats, and a fork's self-checks do NOT substitute \u2014 only the verifier assigns a verdict; you cannot self-assign PARTIAL. Pass the original user request, all files changed (by anyone), the approach, and the plan file path if applicable. Flag concerns if you have them but do NOT share test results or claim things work. On FAIL: fix, resume the verifier with its findings plus your fix, repeat until PASS. On PASS: spot-check it \u2014 re-run 2-3 commands from its report, confirm every PASS has a Command run block with output that matches your re-run. If any PASS lacks a command block or diverges, resume the verifier with the specifics. On PARTIAL (from the verifier): report what passed and what could not be verified.`
       : null,