feat(analysis): implement Golang ABI calling conventions and prologue voting

[doomedraven]

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• I've added tests that prove my changes are effective (required for changes to RZ_API).
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Detailed description
This PR implements native Go calling convention support and automatic ABI detection for compiled Golang binaries across x86-64, ARM64, and x86-32.

Note: This PR is linked to companion rz-ghidra PR: rizinorg/rz-ghidra#395 for Sleigh decompiler prototype integration.

Problem

Previously, Rizin analyzed Go functions using default host C calling conventions (e.g. System V AMD64 or Microsoft x64 with single RAX return).
Go 1.17+ introduced ABIInternal, a register-based calling convention passing up to 9 integer arguments across registers (RAX, RBX, RCX, RDI, RSI, R8, R9, R10, R11) and returning multiple values across registers. Additionally, Go 1.16 and 1.17 share the same pclntab header magic (0xFFFFFFFA), making it difficult to distinguish stack-based ABI0 from register-based ABIInternal when build information is stripped or obfuscated.

Changes

1. Calling Conventions in SDB:
   • librz/arch/types/cc-x86-64.sdb.txt: Added golang (RAX–R11, ret=rax, self=r14) and golang_abi0.
   • librz/arch/types/cc-arm-64.sdb.txt: Added golang (X0–X15, ret=x0, self=x28).
   • librz/arch/types/cc-x86-32.sdb.txt: Added golang (stack, ret=eax).
2. Prologue Voting Heuristic (librz/core/golang.c):
   • Samples the first 24 bytes of recovered Go function prologues to reliably detect active ABI:
     • 49 3B 66 10 / 4D 3B 66 10 (CMPQ SP|R12, 16(R14)): Register ABI (R14 holds g).
     • 65 48|4C 8B /r with SIB 0x25 (MOVQ GS:[disp32], reg): Stack ABI (loads g from TLS).
   • Decisive threshold (>=8 votes, >=90% agreement) resolves the ABI accurately even if build headers are wiped (inspired by heuristics in CAPEmom PR Implement dynamic Go (Golang) stripped symbol recovery and tracing kevoreilly/capemon#181).
3. Symbol Noise Filtering:
   • Filters out compiler-generated thunk wrappers (.abi0, .abiinternal, ..inittask, type:*) from deep function analysis to keep the symbol table clean.
4. Automatic Assignment:
   • Automatically sets fcn->cc = "golang" (or "golang_abi0") on all functions discovered via pclntab.

Test plan

• Ran full test suite: meson test -C build --suite unit -> 138/138 passed.
• Validated with live Go 1.26 binary: aalg correctly detects Register ABI and tags sym.main.* with call-convention: golang.
• Added test in test/db/analysis/golang to check golang calling convention detection.

Closing issues

[doomedraven]

Addressed the early return comment. Tests pass locally.

[doomedraven]

Addressed the minor review comments: used RZ_STR_ISEMPTY and stripped the Rz prefix from the internal struct names.

[doomedraven]

Removed the // Skip compiler-generated thunk wrappers and runtime metadata comment.