Move PTY cleanup to localized error boundaries

Restore provisional PTY size when build-options fails and guard pre-allocated handle registration. This ensures cleanup happens at the point of error, not deferred to the general catch block.

src/main/ipc/pty/ipc/spawn-commit-persist.ts

@@ -84,7 +84,10 @@ export async function persistPtyIpcSpawnCommit(ctx: PtyIpcSpawnState): Promise<{
     })
   }
   if (ctx.preAllocatedHandle && !ctx.stablePaneOwner?.handle) {
-    ctx.deps.runtime?.registerPreAllocatedHandleForPty(ctx.result.id, ctx.preAllocatedHandle)
+    if (ctx.deps.runtime?.registerPreAllocatedHandleForPty) {
+      ctx.deps.runtime.registerPreAllocatedHandleForPty(ctx.result.id, ctx.preAllocatedHandle)
+      ctx.agentTeamsLeaderHandle = null
+    }
   }
   ptySizes.set(ctx.result.id, { cols: args.cols, rows: args.rows })
   if (ctx.effectiveSessionAppId !== undefined && ctx.effectiveSessionAppId !== ctx.result.id) {

src/main/ipc/pty/ipc/spawn-commit.ts

@@ -25,7 +25,6 @@ import { persistPtyIpcSpawnCommit } from './spawn-commit-persist'
 export async function commitPtyIpcSpawn(ctx: PtyIpcSpawnState): Promise<PtySpawnResult> {
   const args = ctx.args
   const { rendererPreSignaled, rendererAlreadyRegistered } = await persistPtyIpcSpawnCommit(ctx)
-  ctx.agentTeamsLeaderHandle = null
 
   // Why: seed the headless emulator before registerPty so concurrent live PTY data lands on top of the seed, not replacing it (mobile keeps the daemon-restored scrollback).
   // Skip when the renderer will be authoritative — its xterm buffer is richer than the daemon snapshot.

src/main/ipc/pty/ipc/spawn-run.ts

@@ -38,7 +38,10 @@ export async function runPtyIpcSpawn(deps: PtySpawnIpcDeps, args: PtySpawnIpcArg
   try {
     await preparePtyIpcSpawnPreflight(ctx)
     await assemblePtyIpcSpawnEnv(ctx)
-    const earlyReserved = await buildPtyIpcSpawnOptions(ctx)
+    const earlyReserved = await buildPtyIpcSpawnOptions(ctx).catch((error: unknown) => {
+      restoreProvisionalPtySize(ctx)
+      throw error
+    })
     if (earlyReserved) {
       // Why: this request lost the pane to the reservation winner, so its
       // pre-allocated leader handle never binds to a PTY. Nothing else can
@@ -51,7 +54,6 @@ export async function runPtyIpcSpawn(deps: PtySpawnIpcDeps, args: PtySpawnIpcArg
     return await commitPtyIpcSpawn(ctx)
   } catch (err) {
     releaseAbandonedAgentTeamsLeader(ctx)
-    restoreProvisionalPtySize(ctx)
     if (ctx.preSpawnHiddenMarkId !== null) {
       ctx.deps.transitionSpawnHiddenRendererPtyDeliveryState(ctx.preSpawnHiddenMarkId, false)
     }

src/main/ipc/pty/runtime/spawn.ts

@@ -87,14 +87,16 @@ export async function spawnPtyFromRuntimeController(
     if (earlyAdopt) {
       return toRuntimeSpawnReply(earlyAdopt)
     }
-    const earlyReserved = await buildRuntimePtySpawnOptions(ctx)
+    const earlyReserved = await buildRuntimePtySpawnOptions(ctx).catch((error: unknown) => {
+      restoreProvisionalPtySize(ctx)
+      throw error
+    })
     if (earlyReserved) {
       return toRuntimeSpawnReply(earlyReserved)
     }
     await executeRuntimePtySpawn(ctx)
     return toRuntimeSpawnReply(await commitRuntimePtySpawn(ctx))
   } catch (err) {
-    restoreProvisionalPtySize(ctx)
     if (ctx.pendingRegistrationPtyId) {
       deps.runtime?.cancelPendingPtyRegistration?.(
         ctx.pendingRegistrationPtyId,