Consolidate duplicate patterns and simplify codebase (#1317)

* refactor(shared): unify binary downloader and session path storage

- Create binary-downloader.ts for common download/extract logic
- Create session-injected-paths.ts for unified path tracking
- Refactor comment-checker, ast-grep, grep downloaders to use shared util
- Consolidate directory injector types into shared module

* feat(shared): implement unified model resolution pipeline

- Create ModelResolutionPipeline for centralized model selection
- Refactor model-resolver to use pipeline
- Update delegate-task and config-handler to use unified logic
- Ensure consistent model resolution across all agent types

* refactor(agents): simplify agent utils and metadata management

- Extract helper functions for config merging and env context
- Register prompt metadata for all agents
- Simplify agent variant detection logic

* cleanup: inline utilities and remove unused exports

- Remove case-insensitive.ts (inline with native JS)
- Simplify opencode-version helpers
- Remove unused getModelLimit, createCompactionContextInjector exports
- Inline transcript entry creation in claude-code-hooks
- Update tests accordingly

---------

Co-authored-by: justsisyphus <justsisyphus@users.noreply.github.com>

src/hooks/claude-code-hooks/transcript.ts

@@ -28,56 +28,6 @@ export function appendTranscriptEntry(
   appendFileSync(path, line)
 }
 
-export function recordToolUse(
-  sessionId: string,
-  toolName: string,
-  toolInput: Record<string, unknown>
-): void {
-  appendTranscriptEntry(sessionId, {
-    type: "tool_use",
-    timestamp: new Date().toISOString(),
-    tool_name: toolName,
-    tool_input: toolInput,
-  })
-}
-
-export function recordToolResult(
-  sessionId: string,
-  toolName: string,
-  toolInput: Record<string, unknown>,
-  toolOutput: Record<string, unknown>
-): void {
-  appendTranscriptEntry(sessionId, {
-    type: "tool_result",
-    timestamp: new Date().toISOString(),
-    tool_name: toolName,
-    tool_input: toolInput,
-    tool_output: toolOutput,
-  })
-}
-
-export function recordUserMessage(
-  sessionId: string,
-  content: string
-): void {
-  appendTranscriptEntry(sessionId, {
-    type: "user",
-    timestamp: new Date().toISOString(),
-    content,
-  })
-}
-
-export function recordAssistantMessage(
-  sessionId: string,
-  content: string
-): void {
-  appendTranscriptEntry(sessionId, {
-    type: "assistant",
-    timestamp: new Date().toISOString(),
-    content,
-  })
-}
-
 // ============================================================================
 // Claude Code Compatible Transcript Builder (PORT FROM DISABLED)
 // ============================================================================