docs(jetbrains): fix Bun Path Hint wording and use Bun.which for bun lookup

Addresses PR review: repairs the broken sentence in the SKILL.md Bun Path
Hint section and replaces the dead 'command -v bun' lookup (not a Bun $
shell builtin) with native Bun.which.

.kilo/skills/jetbrains-cli-pin/SKILL.md

@@ -64,7 +64,7 @@ the only reliable reset.
 
 In repo CLI mode, Gradle's `generateOpenApiSpec` task runs the local CLI source through
 `bun run --conditions=browser ./src/index.ts generate`. IDE-launched Gradle runs can have
-worktree-local hint:
+a stripped `PATH` where `bun` isn't resolvable. The `unpin`/`regen` commands write an ignored, worktree-local hint:
 
 ```text
 packages/kilo-jetbrains/.gradle/kilo-cli-pin.properties

.kilo/skills/jetbrains-cli-pin/script/cli-pin.ts

@@ -53,14 +53,12 @@ async function setPinned(value: boolean) {
   await Bun.write(props, text.replace(/^kilo\.cli\.pinned=.*$/m, `kilo.cli.pinned=${value}`))
 }
 
-async function bunPath() {
-  const result = await $`command -v bun`.quiet().nothrow()
-  const bin = result.exitCode === 0 ? result.stdout.toString().trim() : ""
-  return bin || process.execPath
+function bunPath() {
+  return Bun.which("bun") ?? process.execPath
 }
 
 async function writeBunHint() {
-  const path = await bunPath()
+  const path = bunPath()
   await $`mkdir -p ${jb}/.gradle`
   await Bun.write(hint, `# Generated by jetbrains-cli-pin so IDE-launched Gradle can find Bun in repo CLI mode.\nbun.path=${path}\n`)
   console.log(`Wrote Bun path hint for repo CLI mode: ${path}`)