feat: add experimental support for Podman Quadlet network files to fix errors (Resolves #421)

[SJrX]

Summary

Adds opt-in support for Podman Quadlet .network files, which share the .network extension with systemd-networkd but have a completely different schema.

When enabled, the plugin auto-detects whether a .network file is a Podman Quadlet or systemd-networkd file based on content (e.g., presence of Subnet=, NetworkName= keys vs [Match], [Route] sections), and provides appropriate completions,
inspections, and documentation.

Key changes:

• New PODMAN_NETWORK FileClass with ~18 Podman network keys (Subnet, Gateway, Driver, DisableDNS, etc.) merged at build time with standard [Unit]/[Install]/[Service] sections from systemd
• Auto-detection heuristic in PsiFile.fileClass() that distinguishes Podman Quadlet from systemd-networkd .network files based on section names and keys
• Editor notification banner that appears when a .network file looks like a Podman Quadlet but support is disabled, offering to enable it
• Quick fixes on both "unknown key" warnings and "section not allowed" errors that offer to enable Podman Quadlet support when auto-detection matches
• Settings page at Settings > Tools > systemd Unit Files with an opt-in toggle
• Podman-specific documentation for [Network] section linking to Podman docs instead of systemd-networkd/nspawn docs
• Build pipeline additions: generatePodmanNetworkGperf merges systemd unit gperf data with manually-maintained Podman keys; mergePodmanDocumentation merges Podman JSON docs into the generated documentation JSON

Files added:

• src/main/resources/.../semanticdata/podman/podman-network.gperf — Podman network key definitions
• src/main/resources/.../semanticdata/podman/podman-sectionToKeywordMapFromDoc.json — Podman key documentation
• src/main/kotlin/.../settings/PodmanQuadletSettings.kt — persistent project-level settings
• src/main/kotlin/.../settings/PodmanQuadletConfigurable.kt — settings UI
• src/main/kotlin/.../settings/PodmanNetworkEditorNotificationProvider.kt — editor banner
• src/main/kotlin/.../settings/PodmanQuadletUtil.kt — shared detection helper
• src/main/kotlin/.../intentions/EnablePodmanQuadletSupportQuickFix.kt — quick fix
• 4 test files covering completion, inspections, auto-detection, and quick fixes

Test plan

• ./gradlew test passes (908 tests, 1 pre-existing failure in SemanticDataDocumentationCompletionTest)
• Open a Podman Quadlet .network file with support disabled — blue notification banner appears
• Click "Enable" on the banner — errors/warnings disappear, completions switch to Podman keys
• Hover over [Network] section with CTRL+Q — shows Podman documentation, links to podman.io
• Open a systemd-networkd .network file — no banner, behaves as before
• Disable setting in Settings > Tools > systemd Unit Files — reverts to systemd-networkd behavior

[github-actions]

Test Results

908 tests   908 ✅  41s ⏱️
212 suites    0 💤
212 files      0 ❌

Results for commit 22c2e52.

♻️ This comment has been updated with latest results.