QVAC-21303 infra: simplify SDK e2e target selection

[Victor-Rodzko]

🎯 What problem does this PR solve?

• SDK e2e target selection duplicated long conditions across platform jobs, making the workflow difficult to audit and extend.
• Manual launchers were limited to predefined target combinations instead of being able to select the exact platforms they need.

📝 How does it solve it?

• Replaces the manual target preset dropdown with independent Desktop, Electron, Snap, Android, and iOS checkboxes.
• Defaults to Desktop + Android + iOS, while Electron and Snap remain explicit manual opt-ins.
• Uses concise, human-oriented labels and puts common options before timeouts, device pools, and advanced runner settings.
• Resolves platform selection once and gives each platform job a single boolean condition.
• Preserves every existing reusable-workflow target and keeps PR label-triggered runs limited to desktop + mobile.

🧪 How was it tested?

• actionlint .github/workflows/test-sdk.yml .github/workflows/on-pr-test-sdk.yml
• Verified all 20 manual input descriptions, their order, and platform defaults.
• Exercised all 10 existing reusable target presets and all 5 individual manual platform selections against the actual resolver script.
• Verified empty manual selections fail with an actionable diagnostic.
• git diff --check

[github-actions]

Review Status

Current Status: ❌ PENDING
Approvals so far: none

Pending reviews: Needs 1 Management or Team Lead, and 1 more from Management, Team Lead, or Member.

[github-actions]

License compliance — clean

No new dependency license findings in this PR.

Warn-only (shadow) mode — this check does not block merges yet.

Updated automatically by the canonical license compliance workflow.

NOTICE presence (advisory)

Missing NOTICE (advisory, does not block):

• ./.github/actions/release-merge-guard
• ./packages/vla-ggml/sim/server
• ./packages/transcription-whispercpp/benchmarks/server
• ./packages/embed-llamacpp/benchmarks/performance
• ./packages/embed-llamacpp/benchmarks/server
• ./packages/llm-llamacpp/benchmarks/performance
• ./packages/llm-llamacpp/benchmarks/server
• ./packages/ggml-coload-smoke
• ./packages/sdk/e2e
• ./packages/transcription-parakeet/benchmarks/server
• ./packages/fabric/test/integration
• ./docs/website