Chore: Bump PHPStan to level 7

[loks0n]

Summary

• Adds generic array annotations (array<K, V>) and missing return types across src/ and tests/ to clear level 6.
• Fixes a handful of unchecked string|false / resource|false call sites (file_get_contents, json_encode, ob_get_contents, opendir, Swoole rawContent) for level 7.
• Bumps phpstan.neon from level 5 → 7.

Behaviour

No change on the happy path. The only runtime-visible changes are in previously-broken error paths: opendir() failure now throws instead of passing false into readdir(); FPM getHeader() joins array-valued headers with , instead of returning an array despite a : string return type.

Test plan

• vendor/bin/phpstan analyse — clean at level 7
• vendor/bin/pint --test — passes
• CI on PR

🤖 Generated with Claude Code

[github-actions]

k6 benchmark

Throughput	Requests	Fail rate	p50	p95
7958 req/s	557161	0%	4.68 ms	12.36 ms

[greptile-apps]

Greptile Summary

This PR bumps PHPStan from level 5 to level 7 across src/ and tests/, adding generic array annotations, explicit : void return types, and guards for string|false return sites (file_get_contents, json_encode, ob_get_contents, Swoole rawContent). The two runtime-visible behavior changes — opendir() now throws on failure instead of passing false to readdir(), and FPM getHeader() now joins multi-value headers with ', ' instead of returning an array — are both corrections of previously broken error paths.

Confidence Score: 5/5

Safe to merge — changes are confined to type annotations and previously-broken error paths with no impact on the happy path.

All findings are P2 or below. The annotation-only changes are mechanical and consistent. The two behavioral fixes (opendir throw, FPM header join) are improvements over the prior broken behavior and are documented in the PR description.

No files require special attention.

Important Files Changed

Filename	Overview
phpstan.neon	PHPStan level bumped from 5 to 7; no structural issues.
src/Http/Adapter/FPM/Request.php	getHeader() now joins array-valued headers with ', '; file_get_contents fallback to '' added; array generic annotations updated.
src/Http/Files.php	opendir() failure now throws an Exception instead of silently passing false to readdir().
src/Http/Response.php	json_encode failure now falls back to '' via ?:; getHeaders() return type relaxed to string
src/Http/Adapter/Swoole/Request.php	rawContent() result guarded with ?: '' to handle false return from Swoole.
src/Http/Adapter/Swoole/Server.php	start() return value dropped (now void); onRequest/onStart/start get :void; settings @param annotated.
src/Http/Request.php	Array generics added to all @var/@return/@param; parseContentRange return type narrowed to a typed tuple; file_get_contents guarded.
src/Http/Route.php	$pathParams inner value type corrected from string to int (positions), consistent with Router::preparePath() return type.
src/Http/View.php	ob_get_contents() fallback to '' added; array generics updated for params and filters.
tests/e2e/Client.php	return type narrowed to array; empty-method guard added; @param order in docblock corrected to match actual signature.

_{Reviews (1): Last reviewed commit: "Chore: Bump PHPStan to level 7" | Re-trigger Greptile}