fix(installer): replace silent || true masks with warnings in phase scripts

[boffin-dmytro]

Summary

• Phase 06 (directories): source copy fallback now warns when cp fails instead of silently proceeding with missing files; chmod failures warn that scripts may not be executable; OpenClaw default config copy failure now warns the user
• Phase 11 (services): .env patching loop now checks each awk/cat/rm chain individually and warns on failure instead of always printing success
• Errors are logged to the install log file instead of discarded to /dev/null

Test plan

• Run installer with --dry-run to verify no syntax errors in modified phase scripts
• Verify warnings appear in /tmp/dream-server-install.log when copy/patch operations fail
• Run bash -n on both modified phase scripts to confirm no syntax errors

[Lightheartdevs]

Exactly the right fix — directly addresses the CLAUDE.md rule ("Never || true or 2>/dev/null"). Converts silent failure masks into named warn calls with specific messages ("Source copy incomplete — some files may be missing", etc.) and routes stderr to LOG_FILE for diagnostics.

The awk pipeline refactor in 11-services.sh is a nice bonus: loop-based approach is more readable and lets each key patch report failure independently.

Flag: #953 (BATS tests) appears to carry these same changes. Land this one first, then #953 can rebase cleanly.

[Lightheartdevs]

Focused change, good direction, and current checks are green. Replacing silent masks with visible warnings improves operator feedback without changing the happy path. Approved.