Refactoring debug symbol resolving process on Windows

Present:

• adding wrappers around the DbgHelp API to intercept/report errors
• tracking the "symbol database type" of each module to cull unnecessary work
• scoped lock for DBGHELP_LOCK/UNLOCK
• adding TRACY_SYMBOL_PATH to _NT_SYMBOL_PATH for SymSrv.dll
• decoupling "outer" frame resolve logic from inlined frame resolve logic

Planned for a future PR:

• resolve symbols via DIA (SymGetDiaSession()) whenever possible
• request "bulk" code symbol resolving from cs_disasm() loop