chore: hoist Pi model sort + cover bash-utils edge cases

- Move modelDisplayEntries sort to module scope so it runs once
  instead of on every modelDisplayName call.
- Add bash-utils tests for the env var prefix and true/false
  skip behaviors that came in with the Pi commit.

Verified Pi token semantics against real session data:
input + cacheRead + cacheWrite + output equals totalTokens
exactly, confirming Anthropic-style accounting (cached tokens
disjoint from input). No double-counting.

src/providers/pi.ts

@@ -28,6 +28,9 @@ const toolNameMap: Record<string, string> = {
   patch: 'Patch',
 }
 
+// Pre-sorted by key length descending so longer/more-specific keys match first
+const modelDisplayEntries = Object.entries(modelDisplayNames).sort((a, b) => b[0].length - a[0].length)
+
 type PiEntry = {
   type: string
   id?: string
@@ -200,8 +203,7 @@ export function createPiProvider(sessionsDir?: string): Provider {
     displayName: 'Pi',
 
     modelDisplayName(model: string): string {
-      const entries = Object.entries(modelDisplayNames).sort((a, b) => b[0].length - a[0].length)
-      for (const [key, name] of entries) {
+      for (const [key, name] of modelDisplayEntries) {
         if (model.startsWith(key)) return name
       }
       return model

tests/bash-commands.test.ts

@@ -58,6 +58,21 @@ describe('extractBashCommands', () => {
   it('handles single-quoted separators', () => {
     expect(extractBashCommands("echo 'hello && world'")).toEqual(['echo'])
   })
+
+  it('skips leading env var assignments', () => {
+    expect(extractBashCommands('NODE_ENV=prod npm test')).toEqual(['npm'])
+    expect(extractBashCommands('FOO=bar BAZ=qux ls -la')).toEqual(['ls'])
+  })
+
+  it('skips standalone true/false', () => {
+    expect(extractBashCommands('true && git status')).toEqual(['git'])
+    expect(extractBashCommands('false || echo done')).toEqual(['echo'])
+    expect(extractBashCommands('true')).toEqual([])
+  })
+
+  it('handles env vars combined with chained commands', () => {
+    expect(extractBashCommands('NODE_ENV=test npm test && git push')).toEqual(['npm', 'git'])
+  })
 })
 
 describe('BASH_TOOLS', () => {