Save symbols outside any module to a per-game file, and only save real names

Module symbols are keyed by module+crc so they're shared by every game that
loads that module. But symbols the user attaches to addresses that aren't in
any module - the heap, the stack, scratchpad, a hardware register, typically
after a memory.search - describe one game's own memory layout and are worthless
to any other game. Those now go to PSP/SYSTEM/SYMBOLS/<gameID>_syms.ppsym.

They're module index 0 ("absolute"), which already round-trips through the
existing per-module code: GetModuleRelativeAddr/GetModuleAbsoluteAddr are
identity for it, so the file format is unchanged, just with absolute addresses.
SaveModuleSymbols only needed to stop requiring a ModuleEntry. Auto-load/save
hang off CPU_Init/CPU_Shutdown rather than module load/unload, gated on the same
bAutoSaveLoadSymbols setting - and deliberately not on SYSPROP_HAS_DEBUGGER,
which only the Windows port reports true for, so LoadSymbolsIfSupported next to
it does nothing at all on headless. hle.game.saveSymbols/loadSymbols expose it.

Four things found while doing it:

- Symbols outside any module were being dropped on the floor. AddFunction/
  AddData/AddLabel take moduleIndex -1 as "work it out", pass it to
  GetModuleIndex(), and store whatever comes back - but that returns -1 when no
  module contains the address, and -1 is never an active module, so the symbol
  never reached the active maps: invisible to every lookup and to any save.
  hle.data.add had spotted this and normalized -1 to 0 locally; nothing else
  did, so e.g. hle.func.add outside a module silently did nothing. Fixed
  centrally in a new ResolveModuleIndex() the three of them share.
  (This only became reachable with the GetModuleIndex() fix in 29a38af37e -
  before that it returned a wrong-but-valid module index instead.)

- The saved files were almost entirely noise. Every function the analyzer finds
  is named z_un_<addr> and every import stub zz_<name>, both regenerated from
  scratch on each load. One real module wrote 13KB - 443 unnamed functions and
  64 stub names - for the four names a human had actually chosen. Worse, on the
  next run those were loaded back as authoritative and would beat the module's
  own symbols to the address. Now only names that aren't regenerated get saved,
  and a module with none writes no file at all (and removes a stale one, so
  deleting a symbol sticks). That module's file went 13020 -> 81 bytes.

- LoadModuleSymbols trusted the addresses in the file. It's meant to be
  hand-edited and can outlive the build it came from, so relative addresses past
  the end of the module are now skipped with a warning instead of landing at
  nonsense addresses.

- AddFunction and AddData both erased the map entry they were updating and then
  read back through the now-dangling iterator to refresh the active copy. Only
  latent: the refresh is guarded on the active copy's module matching the new
  one, which is false exactly when the erase happens. Re-point the iterator at
  the entry's new home instead, so it can't rot if that guard ever changes.
  AddLabel already did the equivalent correctly, via a local copy.

Filename sanitizing goes through SanitizeString with a new FileName restriction
rather than being open-coded; unlike the existing restrictions it substitutes
'_' instead of dropping, so two module names can't collapse onto one file.

Verified end to end on headless with cpu_alu.prx: named a function inside the
module and data/functions in scratchpad and the heap, let it exit, checked both
files, rebooted and confirmed all of it came back at the right addresses.
Unit tests 51/51, pspautotests 314/314.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GZq8ZtJmFY7bkX5FVkr3P9

UI/DeveloperToolsScreen.cpp

@@ -201,7 +201,7 @@ void DeveloperToolsScreen::CreateGeneralTab(UI::LinearLayout *list) {
 	CheckBox *localDebugger = list->Add(new CheckBox(&g_Config.bRemoteDebuggerLocal, dev->T("Use locally hosted remote debugger")));
 	localDebugger->SetEnabledPtr(&allowDebugger_);
 
-	list->Add(new CheckBox(&g_Config.bAutoSaveLoadSymbols, dev->T("Auto save/load module symbols")));
+	list->Add(new CheckBox(&g_Config.bAutoSaveLoadSymbols, dev->T("Auto save/load symbols")));
 
 	list->Add(new Choice(dev->T("GPI/GPO switches/LEDs")))->OnClick.Add([=](UI::EventParams &e) {
 		screenManager()->push(new GPIGPOScreen(dev->T("GPI/GPO switches/LEDs")));