fix(hooks): Route hook templates to Dolt-aware implementations

- Fix infinite recursion bug in computeJSONLHashForHook (was calling
  itself instead of computeJSONLHash)
- Update pre-commit, post-merge, post-checkout templates to use
  `bd hook <name>` instead of `bd hooks run <name>`, routing to the
  Dolt-aware implementations in hook.go
- Update all hook template versions to 0.48.0 for consistency

The hook infrastructure added in 15d74a9a had a critical bug where
the hash computation function recursed infinitely, and the templates
still pointed to the old hook implementations in hooks.go instead
of the new Dolt-aware ones in hook.go.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/bd/hook.go

@@ -129,7 +129,7 @@ func saveExportState(beadsDir, worktreeRoot string, state *ExportState) error {
 // computeJSONLHashForHook computes a hash of the JSONL file contents for hook state tracking.
 // This is a wrapper around computeJSONLHash that handles missing files gracefully.
 func computeJSONLHashForHook(jsonlPath string) (string, error) {
-	hash, err := computeJSONLHashForHook(jsonlPath)
+	hash, err := computeJSONLHash(jsonlPath)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return "", nil