fix: use ctx.directory instead of process.cwd() in tools for Desktop app support

Convert grep, glob, ast-grep, and session-manager tools from static exports to factory functions that receive PluginInput context. This allows them to use ctx.directory instead of process.cwd(), fixing issue #658 where tools search from wrong directory in OpenCode Desktop app.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/tools/ast-grep/index.ts

@@ -1,12 +1,4 @@
-import type { ToolDefinition } from "@opencode-ai/plugin"
-import { ast_grep_search, ast_grep_replace } from "./tools"
-
-export const builtinTools: Record<string, ToolDefinition> = {
-  ast_grep_search,
-  ast_grep_replace,
-}
-
-export { ast_grep_search, ast_grep_replace }
+export { createAstGrepTools } from "./tools"
 export { ensureAstGrepBinary, getCachedBinaryPath, getCacheDir } from "./downloader"
 export { getAstGrepPath, isCliAvailable, ensureCliAvailable, startBackgroundInit } from "./cli"
 export { checkEnvironment, formatEnvironmentCheck } from "./constants"