UI: password change enforcement + migration recovery

- Web UI admin password reset now enforces admin role
  server-side (was cookie-auth + CSRF only; any logged-in
  user could previously reset any account's password)
- Added self-service password change UI at GET/PUT /profile:
  current_password + new_password + confirm_password;
  server-side equality check; lockout + Argon2id verification;
  revokes all other sessions on success
- password_change_form.html fragment and profile.html page
- Nav bar actor name now links to /profile
- policy: ActionChangePassword + default rule -7 allowing
  human accounts to change their own password
- openapi.yaml: built-in rules count updated to -7

Migration recovery:
- mciasdb schema force --version N: new subcommand to clear
  dirty migration state without running SQL (break-glass)
- schema subcommands bypass auto-migration on open so the
  tool stays usable when the database is dirty
- Migrate(): shim no longer overrides schema_migrations
  when it already has an entry; duplicate-column error on
  the latest migration is force-cleaned and treated as
  success (handles columns added outside the runner)

Security:
- Admin role is now validated in handleAdminResetPassword
  before any DB access; non-admin receives 403
- handleSelfChangePassword follows identical lockout +
  constant-time Argon2id path as the REST self-service
  handler; current password required to prevent
  token-theft account takeover

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

internal/ui/handlers_accounts.go

@@ -901,10 +901,32 @@ func (u *UIServer) handleCreatePGCreds(w http.ResponseWriter, r *http.Request) {
 // for the target account are revoked so a compromised account is fully
 // invalidated.
 //
-// Security: new password is validated (minimum 12 chars) and hashed with
-// Argon2id before storage.  The plaintext is never logged or included in any
-// response.  Audit event EventPasswordChanged is recorded on success.
+// Security: caller must hold the admin role; the check is performed server-side
+// against the JWT claims so it cannot be bypassed by client-side tricks.
+// New password is validated (minimum 12 chars) and hashed with Argon2id before
+// storage.  The plaintext is never logged or included in any response.
+// Audit event EventPasswordChanged is recorded on success.
 func (u *UIServer) handleAdminResetPassword(w http.ResponseWriter, r *http.Request) {
+	// Security: enforce admin role; requireCookieAuth only validates the token,
+	// it does not check roles.  A non-admin with a valid session must not be
+	// able to reset arbitrary accounts' passwords.
+	callerClaims := claimsFromContext(r.Context())
+	if callerClaims == nil {
+		u.renderError(w, r, http.StatusUnauthorized, "unauthorized")
+		return
+	}
+	isAdmin := false
+	for _, role := range callerClaims.Roles {
+		if role == "admin" {
+			isAdmin = true
+			break
+		}
+	}
+	if !isAdmin {
+		u.renderError(w, r, http.StatusForbidden, "admin role required")
+		return
+	}
+
 	r.Body = http.MaxBytesReader(w, r.Body, maxFormBytes)
 	if err := r.ParseForm(); err != nil {
 		u.renderError(w, r, http.StatusBadRequest, "invalid form")