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/shared/agent-tool-restrictions.ts

@@ -4,8 +4,6 @@
  * true = tool allowed, false = tool denied.
  */
 
-import { findCaseInsensitive } from "./case-insensitive"
-
 const EXPLORATION_AGENT_DENYLIST: Record<string, boolean> = {
   write: false,
   edit: false,
@@ -37,10 +35,13 @@ const AGENT_RESTRICTIONS: Record<string, Record<string, boolean>> = {
 }
 
 export function getAgentToolRestrictions(agentName: string): Record<string, boolean> {
-  return findCaseInsensitive(AGENT_RESTRICTIONS, agentName) ?? {}
+  return AGENT_RESTRICTIONS[agentName]
+    ?? Object.entries(AGENT_RESTRICTIONS).find(([key]) => key.toLowerCase() === agentName.toLowerCase())?.[1]
+    ?? {}
 }
 
 export function hasAgentToolRestrictions(agentName: string): boolean {
-  const restrictions = findCaseInsensitive(AGENT_RESTRICTIONS, agentName)
+  const restrictions = AGENT_RESTRICTIONS[agentName]
+    ?? Object.entries(AGENT_RESTRICTIONS).find(([key]) => key.toLowerCase() === agentName.toLowerCase())?.[1]
   return restrictions !== undefined && Object.keys(restrictions).length > 0
 }