fix(windows): skip DPI awareness API call when already set via manifest

[leaanthony]

Summary

• Check current DPI awareness before calling SetProcessDpiAwarenessContext
• Windows only allows setting DPI awareness once per process - either via manifest or API, not both
• If already set (e.g., via application manifest in built binaries), skip the API call to avoid "Access is denied" errors

Problem

When using wails3 dev or running built binaries, users see the error:

SetProcessDpiAwarenessContext failed 0: 18446744073709551612 Access is denied.

This happens because:

1. Built binaries have a manifest file that sets DPI awareness
2. At runtime, setupDPIAwareness() tries to call SetProcessDpiAwarenessContext
3. Windows rejects the API call since DPI awareness was already configured

Solution

Added GetProcessDpiAwareness() to query the current DPI awareness level before attempting to set it. If awareness is already configured (not PROCESS_DPI_UNAWARE), the API call is skipped.

Test plan

• Build a Wails app with wails3 build and verify no DPI error appears
• Run with go run and verify DPI awareness is correctly set via API
• Test on Windows 10/11 with various DPI settings

Fixes #4803

🤖 Generated with Claude Code

Summary by CodeRabbit

• New Features
  • Added runtime DPI-awareness detection so the app can determine current DPI configuration before adjusting settings.
• Bug Fixes
  • Prevents an "Access is denied" error at startup when DPI awareness is already set (e.g., via application manifest) by skipping redundant reconfiguration.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

Caution

Review failed

The pull request is closed.

Walkthrough

Adds a pre-check to skip setting DPI awareness if already configured (e.g., via app manifest) and exposes GetProcessDpiAwareness bindings to query current DPI awareness from shcore.dll, preventing "Access is denied" errors when DPI is pre-set.

Changes

Cohort / File(s)	Summary
Changelog entry v3/UNRELEASED_CHANGELOG.md	Documents bug fix: avoid "Access is denied" from SetProcessDpiAwarenessContext when DPI awareness is already set
DPI awareness pre-check v3/pkg/application/application_windows.go	Adds early-return in setupDPIAwareness: if GetProcessDpiAwareness reports a set state (not PROCESS_DPI_UNAWARE), skip subsequent SetProcessDpiAwarenessContext/SetProcessDpiAwareness calls
Windows API bindings v3/pkg/w32/shcore.go	Adds procGetProcessDpiAwareness, HasGetProcessDpiAwarenessFunc(), and GetProcessDpiAwareness() to query process DPI awareness at runtime

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Suggested labels

Bug, go, Windows, v3-alpha, size:M

Poem

🐰 I peeked at DPI with a twitchy nose,
If manifest set it, I quietly doze.
No more denied—just a gentle hop,
Skipping the call, and I’m off to the crop. 🥕✨

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 25.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: adding a check to skip DPI awareness API calls when already set via manifest, which directly addresses the fix for issue #4803.
Description check	✅ Passed	The description includes a clear summary of the problem and solution, references the fixed issue (#4803), and provides a test plan. Most template sections are addressed, though some checklist items are not explicitly confirmed.
Linked Issues check	✅ Passed	The PR successfully addresses issue #4803 by implementing GetProcessDpiAwareness() to check current DPI awareness and skip redundant API calls, preventing 'Access is denied' errors when DPI awareness is already set via application manifest.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to fixing the DPI awareness issue: additions to the Windows bindings (w32/shcore.go), modifications to DPI setup logic (application_windows.go), and changelog documentation.

✨ Finishing touches

• 📝 Generate docstrings

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Latest commit:	a4a2fbe
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View logs

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud