merge: sync upstream profanity-im/profanity

Sync with upstream profanity-im/profanity.

Major upstream changes incorporated:

Memory management
  - Replace malloc+memset with g_new0 throughout codebase
  - Adopt auto_gchar / auto_gcharv / auto_gerror / auto_jid cleanup macros
  - Replace free() with g_free() for GAlloc'd memory

Editor rewrite
  - Remove pthread-based async editor; use GChildWatch callback API
  - New launch_editor(initial_content, callback, user_data) interface
  - Proper signal handling (SIGINT, SIGTSTP, SIGPIPE reset in child)
  - ui_suspend()/ui_resume() integration for TTY management

OMEMO improvements
  - Dual backend support: libsignal-protocol-c and libomemo-c
  - Proper pre-key removal after use (XEP-0384 compliance)
  - Automatic pre-key regeneration when store drops below threshold
  - New functions: omemo_is_device_active(), omemo_is_jid_trusted()
  - omemo_get_jid_untrusted_fingerprints() for better error messages
  - Fingerprint notifications on new device identity discovery
  - Deterministic pre-key ID generation tracking max_pre_key_id
  - omemo_trust_changed() UI updates on trust state changes

JID validation
  - RFC 6122-compliant validation in jid_is_valid()
  - Character-level checks (RFC 6122 forbidden chars: & ' / : < > @)
  - Length limits: 1023 per component, 3071 total
  - New jid_is_valid_user_jid() for user vs. service JID distinction

Database
  - Schema migration v3: UNIQUE constraint on archive_id for deduplication
  - Triggers for corrected message tracking (replaces_db_id / replaced_by_db_id)
  - db_history_result_t return type, _truncate_datetime_suffix()

UI / console
  - win_warn_needed() / win_warn_sent() warning deduplication hash table
  - PAD_MIN_HEIGHT dynamic pad sizing with PAD_THRESHOLD auto-cleanup
  - Spellcheck integration in input field with Unicode word detection
  - cons_spellcheck_setting() for /settings ui output
  - /[command]? shortcut for command help

Account config
  - Account name sanitization for GKeyFile special chars ([ ] = # \n \r)
  - Replace popen() with g_spawn_sync() for eval_password
  - TLS policy: add "direct" option alongside legacy

Connection
  - Port validation with g_assert (0–65535)
  - SHA-256 certificate fingerprint support (XMPP_CERT_PUBKEY_FINGERPRINT_SHA256)
  - "direct" TLS policy alias for legacy SSL

Common utilities
  - str_xml_sanitize() for XML 1.0 illegal character removal
  - string_matches_one_of() with formatted error messages
  - valid_tls_policy_option() helper
  - prof_date_time_format_iso8601() utility
  - Improved strip_arg_quotes() with backslash unescaping
  - prof_occurrences() uses g_slist_prepend + reverse for performance

PGP / OX
  - Proper GPGME resource cleanup with goto-cleanup pattern
  - g_string_free(xmppuri) leak fix in _ox_key_lookup

CSV export
  - Use GString + g_file_set_contents instead of raw write() syscalls

Tests
  - Restructured into subdirectories: command/, config/, xmpp/, ui/, omemo/, otr/, pgp/
  - New test_cmd_ac.c for autocompleter unit tests
  - Updated stubs for new UI suspend/resume functions

License headers
  - Migrate to SPDX-3.0 identifiers (GPL-3.0-or-later WITH OpenSSL-exception)

────────────────────────────────────────────────────
cproof-specific preservations:

  - XEP-0308 LMC: replace_id ?: id logic in message/stanza/omemo
  - Force encryption: cmd_force_encryption, test_forced_encryption
  - CWE-134: format string protection (cons_show("%s", ...))
  - y_start_pos-based paging in window.c
  - db_history_result_t return type, _truncate_datetime_suffix()

Merge-time fixes:

  - common.c: format-security (-Werror) — cons_show(errmsg) → cons_show("%s", errmsg)
  - database.c: null-deref guard — !msg->timestamp → msg && !msg->timestamp
  - console.c: implicit size_t → int cast — (int)(maxlen + 1)
  - tlscerts.c: %d for size_t — %zu

Build system:
  - Kept autotools (Makefile.am, configure.ac); upstream uses Meson
  - Restored deleted files: bootstrap.sh, autogen.sh, ax_valgrind_check.m4, configure-debug
  - Updated Makefile.am test paths for subdirectory structure
  - Added test_cmd_ac, test_forced_encryption to test sources

Functional tests:
  - Use cproof version; upstream requires stbbr_for_xmlns from updated stabber
  - Not yet available in devs/stabber fork

Closes #64

Merge author: jabber.developer2
Commits authors:
 Michael Vetter <jubalh@iodoru.org>
& Steffen Jaeckel <s@jaeckel.eu>

src/xmpp/stanza.c

@@ -4,33 +4,7 @@
  *
  * Copyright (C) 2012 - 2019 James Booth <boothj5@gmail.com>
  *
- * This file is part of Profanity.
- *
- * Profanity is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * Profanity is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Profanity.  If not, see <https://www.gnu.org/licenses/>.
- *
- * In addition, as a special exception, the copyright holders give permission to
- * link the code of portions of this program with the OpenSSL library under
- * certain conditions as described in each individual source file, and
- * distribute linked combinations including the two.
- *
- * You must obey the GNU General Public License in all respects for all of the
- * code used other than OpenSSL. If you modify file(s) with this exception, you
- * may extend this exception to your version of the file(s), but you are not
- * obligated to do so. If you do not wish to do so, delete this exception
- * statement from your version. If you delete this exception statement from all
- * source files in the program, then also delete it here.
- *
+ * SPDX-License-Identifier: GPL-3.0-or-later WITH OpenSSL-exception
  */
 
 #include "config.h"
@@ -221,8 +195,14 @@ stanza_create_http_upload_request(xmpp_ctx_t* ctx, const char* const id,
     xmpp_stanza_set_ns(request, STANZA_NS_HTTP_UPLOAD);
 
     auto_char char* filename_cpy = strdup(upload->filename);
+    if (!filename_cpy) {
+        xmpp_stanza_release(iq);
+        xmpp_stanza_release(request);
+        return NULL;
+    }
+
     // strip spaces from filename (servers don't spaces)
-    for (int i = 0; i < strlen(filename_cpy); i++) {
+    for (size_t i = 0; i < strlen(filename_cpy); i++) {
         if (filename_cpy[i] == ' ') {
             filename_cpy[i] = '_';
         }
@@ -1690,7 +1670,7 @@ stanza_parse_caps(xmpp_stanza_t* const stanza)
     const char* node = xmpp_stanza_get_attribute(caps_st, STANZA_ATTR_NODE);
     const char* ver = xmpp_stanza_get_attribute(caps_st, STANZA_ATTR_VER);
 
-    XMPPCaps* caps = (XMPPCaps*)malloc(sizeof(XMPPCaps));
+    XMPPCaps* caps = g_new0(XMPPCaps, 1);
     caps->hash = hash ? strdup(hash) : NULL;
     caps->node = node ? strdup(node) : NULL;
     caps->ver = ver ? strdup(ver) : NULL;
@@ -1863,7 +1843,7 @@ stanza_get_error_message(xmpp_stanza_t* stanza)
             STANZA_NAME_UNEXPECTED_REQUEST
         };
 
-        for (int i = 0; i < ARRAY_SIZE(defined_conditions); i++) {
+        for (size_t i = 0; i < ARRAY_SIZE(defined_conditions); i++) {
             xmpp_stanza_t* cond_stanza = xmpp_stanza_get_child_by_name(error_stanza, defined_conditions[i]);
             if (cond_stanza) {
                 char* result = strdup(xmpp_stanza_get_name(cond_stanza));
@@ -2134,7 +2114,7 @@ stanza_parse_presence(xmpp_stanza_t* stanza, int* err)
         return NULL;
     }
 
-    XMPPPresence* result = (XMPPPresence*)malloc(sizeof(XMPPPresence));
+    XMPPPresence* result = g_new0(XMPPPresence, 1);
     result->jid = from_jid;
 
     result->show = stanza_get_show(stanza, "online");