Fix type performance comment permission

[SandroMaglione]

Summary

• Grant the type-performance report workflow write access to pull requests.
• Fix the 403 returned when the trusted workflow_run job creates or updates its PR comment.

The benchmark, artifact download, and report rendering already succeeded. Only the final PR timeline comment was rejected because the job had pull-requests: read.

Changeset

• Added or updated for a library or package-metadata change
• Not required because this PR does not change src/ or package.json

Validation

• pnpm check
• Relevant example checks, when examples changed (not applicable; no examples changed)
• Reviewed the automated type-performance report, when the public TypeScript API or inference changed (not applicable; no TypeScript API change)

[github-actions]

Type performance

Measured with TypeScript 6.0.3 and skipLibCheck=true.

Scenario	Base	PR	Difference
Effect only	55	55	0 (0.0%)
Import effect-machine	55	55	0 (0.0%)
Machine.defineStates (3 states)	2,902	2,902	0 (0.0%)
Machine.make (3 states, 2 events)	8,668	8,668	0 (0.0%)
machine.handle (3 states, 2 transitions)	23,474	23,474	0 (0.0%)
machine.handle (depth 8)	112,138	112,138	0 (0.0%)
machine.handle (depth 12)	124,580	124,580	0 (0.0%)
machine.handle (depth 16)	139,726	139,726	0 (0.0%)
machine.handle (depth 24)	178,130	178,130	0 (0.0%)
machine.handle (wide depth 16)	208,161	208,161	0 (0.0%)

Marginal instantiations are measured against the matching setup without that API call:

Scenario	Base	PR	Difference
Import effect-machine	0	0	0
Machine.defineStates (3 states)	2,847	2,847	0 (0.0%)
Machine.make (3 states, 2 events)	5,758	5,758	0 (0.0%)
machine.handle (3 states, 2 transitions)	14,806	14,806	0 (0.0%)
machine.handle (depth 8)	105,202	105,202	0 (0.0%)
machine.handle (depth 12)	116,640	116,640	0 (0.0%)
machine.handle (depth 16)	130,782	130,782	0 (0.0%)
machine.handle (depth 24)	167,178	167,178	0 (0.0%)
machine.handle (wide depth 16)	197,825	197,825	0 (0.0%)

Check times (informational)

Scenario	Base	PR
Effect only	0.03s	0.03s
Import effect-machine	0.03s	0.03s
Machine.defineStates (3 states)	0.09s	0.09s
Machine.make (3 states, 2 events)	0.14s	0.15s
machine.handle (3 states, 2 transitions)	0.23s	0.23s
machine.handle (depth 8)	0.49s	0.51s
machine.handle (depth 12)	0.55s	0.52s
machine.handle (depth 16)	0.56s	0.58s
machine.handle (depth 24)	0.65s	0.65s
machine.handle (wide depth 16)	0.69s	0.69s

Type instantiations are the comparison metric. Check time varies with runner load and is informational only.