Fix: Enterprise cluster restore (postgres user via su)

Critical fixes for enterprise environments where dbbackup runs as
postgres user via 'su postgres' without sudo access:

1. canRestartPostgreSQL(): New function that detects if we can restart
   PostgreSQL. Returns false immediately if running as postgres user
   without sudo access, avoiding wasted time and potential hangs.

2. tryRestartPostgreSQL(): Now calls canRestartPostgreSQL() first to
   skip restart attempts in restricted environments.

3. Changed restart warning from ERROR to WARN level - it's expected
   behavior in enterprise environments, not an error.

4. Context cancellation check: Goroutines now check ctx.Err() before
   starting and properly count cancelled databases as failures.

5. Goroutine accounting: After wg.Wait(), verify all databases were
   accounted for (success + fail = total). Catches goroutine crashes
   or deadlocks.

6. Port argument fix: Always pass -p port to psql for localhost
   restores, fixing non-standard port configurations.

This should fix the issue where cluster restore showed success but
0 databases were actually restored when running on enterprise systems.

bin/README.md

@@ -4,8 +4,8 @@ This directory contains pre-compiled binaries for the DB Backup Tool across mult
 
 ## Build Information
 - **Version**: 3.42.34
-- **Build Time**: 2026-01-16_12:52:56_UTC
-- **Git Commit**: 62ddc57
+- **Build Time**: 2026-01-16_13:03:20_UTC
+- **Git Commit**: 3201f0f
 
 ## Recent Updates (v1.1.0)
 - ✅ Fixed TUI progress display with line-by-line output