fix: change delete swap from 'delete' to 'outerHTML' to avoid CSS selector issues

The export IDs contain special characters (colons and slashes from DIDs)
that are invalid in CSS selectors. Changed from:
- hx-target="#export-{{.ID}}" with hx-swap="delete"

To:
- hx-target="closest tr" with hx-swap="outerHTML"

This avoids the querySelectorAll syntax error while still properly
removing the table row when the delete succeeds.

Fixes: SyntaxError: '#export-did:plc:...' is not a valid selector

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[e-mail]>

internal/web/handlers/export.go

···
 	h.logger.Printf("Delete completed: user=%s export=%s",
 		session.DID, exportID)
 
-	// Return 200 OK with empty body for HTMX delete swap
-	// The hx-swap="delete" will remove the target element on 2xx response
+	// Return 200 OK with empty body for HTMX outerHTML swap
+	// The hx-swap="outerHTML" with empty response will remove the target element
 	w.WriteHeader(http.StatusOK)
 	w.Write([]byte{})
 }

internal/web/templates/pages/export.html

···
                                             style="margin: 0;"
                                             hx-delete="/export/delete/{{.ID}}"
                                             hx-confirm="Are you sure you want to delete this export? This action cannot be undone."
-                                            hx-target="#export-{{.ID}}"
-                                            hx-swap="delete"
+                                            hx-target="closest tr"
+                                            hx-swap="outerHTML"
                                             hx-headers='{"X-CSRF-Token": "{{$.CSRFToken}}"}'>
                                         Delete
                                     </button>