fix: CWE-134 format string audit and compiler hardening

Security:
Fix CWE-134 in iq.c: user-controlled string passed as format argument
Add G_GNUC_PRINTF annotations to all variadic printf-like wrappers
in ui.h, log.h and http_common.h
Compiler flags (configure.ac):

Replace basic -Wformat/-Wformat-nonliteral with -Wformat=2
Add -Wextra, -Wnull-dereference, -Wpointer-arith,
-Wimplicit-function-declaration, -Wundef, -Wfloat-equal,
-Wredundant-decls, -Walloc-zero
Add -fstack-protector-strong, -fno-common, -D_FORTIFY_SOURCE=2
Add GCC-specific flags via AC_COMPILE_IFELSE: -Wlogical-op,
-Wduplicated-cond, -Wduplicated-branches, -Wstringop-overflow,
-Warray-bounds=2
Suppress noisy -Wextra sub-warnings: -Wno-unused-parameter,
-Wno-missing-field-initializers, -Wno-sign-compare,
-Wno-cast-function-type
Remove AM_CFLAGS/CFLAGS duplication
Bug fixes found by new warnings:

chatlog.c: non-MUCPM redact path passed resourcepart instead of NULL
rosterwin.c: merge duplicated if/else branches into single condition
omemo.c: redundant else-if in omemo_automatic_start; remove
unnecessary scope block and goto, use early return
console.c: pointer compared to integer 0 instead of NULL
stanza.c: increase pri_str/idle_str buffers from 10 to 12 bytes
(INT_MIN = -2147483648 needs 12 bytes including NUL)
vcard.c: NULL guard for filename before g_file_set_contents
api.c: broken log_warning() calls with extra format argument
Format mismatch fixes:

chatwin.c: Jid* → char* for %s
connection.c: %x → %lx for long flags
cmd_funcs.c: %d → %zu for size_t; cast gpointer to char* for %s
cmd_defs.c: %d → %u for g_list_length() return (guint)
iq.c: barejid → fulljid for from_jid
console.c, mucwin.c, privwin.c, account.c, omemo.c, presence.c:
gpointer → (char*) casts for %s
Const-correctness and cleanup:

database.c: const for type, query, sort variables
form.c/xmpp.h: const for form_set_value parameter
files.c: refactor to early return, eliminating NULL logfile path
muc.c/muc.h: remove meaningless top-level const on return type
common.c: const for URL string literal
Remove stale declarations: cons_show_desktop_prefs (ui.h),
connection_set_priority (connection.h),
omemo_devicelist_configure_and_request (omemo.h)
test_common.c: add currb NULL check to silence -Wnull-dereference
Tooling (check-cwe134.sh):

Reduce from 5 checks to 2 (checks 1-3 redundant with -Wformat=2)
Check 1: verify known wrappers have G_GNUC_PRINTF attribute
Check 2: auto-detect unannotated variadic printf-like functions
Match both const char* and const gchar* in variadic patterns

Author: jabber.developer2 <jabber.developer2@jabber.space>

src/database.c

@@ -55,7 +55,7 @@
 
 static sqlite3* g_chatlog_database;
 
-static void _add_to_db(ProfMessage* message, char* type, const Jid* const from_jid, const Jid* const to_jid);
+static void _add_to_db(ProfMessage* message, const char* type, const Jid* const from_jid, const Jid* const to_jid);
 static char* _get_db_filename(ProfAccount* account);
 static prof_msg_type_t _get_message_type_type(const char* const type);
 static prof_enc_t _get_message_enc_type(const char* const encstr);
@@ -167,22 +167,22 @@ log_database_init(ProfAccount* account)
     // replace_id is the ID from XEP-0308: Last Message Correction
     // replaces_db_id is ID (primary key) of the original message that LMC message corrects/replaces
     // replaced_by_db_id is ID (primary key) of the last correcting (LMC) message for the original message
-    char* query = "CREATE TABLE IF NOT EXISTS `ChatLogs` ("
-                  "`id` INTEGER PRIMARY KEY AUTOINCREMENT, "
-                  "`from_jid` TEXT NOT NULL, "
-                  "`to_jid` TEXT NOT NULL, "
-                  "`from_resource` TEXT, "
-                  "`to_resource` TEXT, "
-                  "`message` TEXT, "
-                  "`timestamp` TEXT, "
-                  "`type` TEXT, "
-                  "`stanza_id` TEXT, "
-                  "`archive_id` TEXT, "
-                  "`encryption` TEXT, "
-                  "`marked_read` INTEGER, "
-                  "`replace_id` TEXT, "
-                  "`replaces_db_id` INTEGER, "
-                  "`replaced_by_db_id` INTEGER)";
+    const char* query = "CREATE TABLE IF NOT EXISTS `ChatLogs` ("
+                        "`id` INTEGER PRIMARY KEY AUTOINCREMENT, "
+                        "`from_jid` TEXT NOT NULL, "
+                        "`to_jid` TEXT NOT NULL, "
+                        "`from_resource` TEXT, "
+                        "`to_resource` TEXT, "
+                        "`message` TEXT, "
+                        "`timestamp` TEXT, "
+                        "`type` TEXT, "
+                        "`stanza_id` TEXT, "
+                        "`archive_id` TEXT, "
+                        "`encryption` TEXT, "
+                        "`marked_read` INTEGER, "
+                        "`replace_id` TEXT, "
+                        "`replaces_db_id` INTEGER, "
+                        "`replaced_by_db_id` INTEGER)";
     if (SQLITE_OK != sqlite3_exec(g_chatlog_database, query, NULL, 0, &err_msg)) {
         goto out;
     }
@@ -272,7 +272,7 @@ log_database_add_incoming(ProfMessage* message)
 }
 
 static void
-_log_database_add_outgoing(char* type, const char* const id, const char* const barejid, const char* const message, const char* const replace_id, prof_enc_t enc)
+_log_database_add_outgoing(const char* type, const char* const id, const char* const barejid, const char* const message, const char* const replace_id, prof_enc_t enc)
 {
     ProfMessage* msg = message_init();
 
@@ -379,8 +379,8 @@ log_database_get_previous_chat(const gchar* const contact_barejid, const gchar*
     }
 
     // Flip order when querying older pages
-    gchar* sort1 = from_start ? "ASC" : "DESC";
-    gchar* sort2 = !flip ? "ASC" : "DESC";
+    const gchar* sort1 = from_start ? "ASC" : "DESC";
+    const gchar* sort2 = !flip ? "ASC" : "DESC";
     GDateTime* now = g_date_time_new_now_local();
     auto_gchar gchar* end_date_fmt = end_time ? g_strdup(end_time) : g_date_time_format_iso8601(now);
     auto_sqlite gchar* query = sqlite3_mprintf("SELECT * FROM ("
@@ -499,7 +499,7 @@ _get_message_enc_type(const char* const encstr)
 }
 
 static void
-_add_to_db(ProfMessage* message, char* type, const Jid* const from_jid, const Jid* const to_jid)
+_add_to_db(ProfMessage* message, const char* type, const Jid* const from_jid, const Jid* const to_jid)
 {
     auto_gchar gchar* pref_dblog = prefs_get_string(PREF_DBLOG);
     sqlite_int64 original_message_id = -1;