feat: rework runner config to INI format with full field support

Replace pipe-delimited runners.conf with INI-style sections supporting
host resolution, container images, repo-scoped tokens, resource limits,
capacity, and SSH key passthrough. All defaults pulled from .env.

- Add INI parsing helpers (ini_list_sections, ini_get, ini_set) to common.sh
- Add SSH key support (UNRAID_SSH_KEY, FEDORA_SSH_KEY) to ssh_exec/scp_to
- Add .env vars: RUNNER_DEFAULT_IMAGE, RUNNER_DEFAULT_CAPACITY,
  RUNNER_DEFAULT_DATA_PATH, LOCAL_RUNNER_DATA_PATH, LOCAL_REGISTRY
- Rewrite manage_runner.sh with host/image/token resolution and resource limits
- Rewrite configure_runners.sh wizard for INI format with all 9 fields
- Update phase3 scripts to use ini_list_sections instead of pipe parsing
- Add runners.conf INI validation to preflight.sh (check 5b)
- Update templates to use resolved labels, capacity, and deploy resources

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

phase3_runners.sh

@@ -29,8 +29,8 @@ if [[ ! -f "$RUNNERS_CONF" ]]; then
   exit 1
 fi
 
-# Count non-comment, non-blank lines to verify there are runners to deploy
-RUNNER_COUNT=$(grep -Evc '^[[:space:]]*($|#)' "$RUNNERS_CONF")
+# Count INI sections to verify there are runners to deploy
+RUNNER_COUNT=$(ini_list_sections "$RUNNERS_CONF" | wc -l | xargs)
 if [[ "$RUNNER_COUNT" -eq 0 ]]; then
   log_error "No runners defined in runners.conf"
   exit 1
@@ -63,8 +63,7 @@ fi
 
 # ---------------------------------------------------------------------------
 # Step 2: Deploy each runner via manage_runner.sh
-# Iterates over every non-comment line in runners.conf, extracts the name
-# (first pipe-delimited field), and invokes manage_runner.sh add.
+# Iterates over every INI section in runners.conf (each section = one runner).
 # manage_runner.sh handles its own idempotency (skips already-running runners).
 # ---------------------------------------------------------------------------
 log_step 2 "Deploying runners..."
@@ -72,12 +71,8 @@ log_step 2 "Deploying runners..."
 DEPLOYED=0
 FAILED=0
 
-while IFS='|' read -r name rest; do
-  # Skip comments and blank lines
-  [[ "$name" =~ ^[[:space:]]*# ]] && continue
+while IFS= read -r name; do
   [[ -z "$name" ]] && continue
-
-  name=$(echo "$name" | xargs)
   log_info "Processing runner: ${name}"
 
   if "${SCRIPT_DIR}/manage_runner.sh" add --name "$name"; then
@@ -86,7 +81,7 @@ while IFS='|' read -r name rest; do
     log_error "Failed to deploy runner: ${name}"
     FAILED=$((FAILED + 1))
   fi
-done < "$RUNNERS_CONF"
+done < <(ini_list_sections "$RUNNERS_CONF")
 
 # ---------------------------------------------------------------------------
 # Summary