*11949
webif: remove poll from request read loop
Simplify WebIf request handling by relying on check_request()
to detect complete HTTP headers and request bodies instead of
polling the socket between reads.
This removes the extra poll-based wait path while preserving
correct handling for fragmented GET and POST requests.
thx to @lpm11
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*11948
Extend service and group handling to 128 entries and harden related limits
Add platform-aware 128-bit group and service support for builds with __int128, while preserving correct 64-bit fallback behavior.
- introduce group_t and GROUP_BITS so group and sidtab bitmasks scale to 128 entries where supported
- enforce MAX_SIDBITS consistently across parsing, runtime checks, and WebIF handling
- fix off-by-one, buffer sizing, and numbering issues in group and service serialization
- improve validation, truncation handling, and warning messages for invalid or oversized group/service definitions
- add and document the httpmaxrequestsize config option, and make WebIF request parsing enforce the configured limit
- add clearer startup diagnostics for effective group/service capacity and ABI details
- update WebIF limits and documentation to reflect build-dependent 64 or 128 entry support
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*11947
chore: align README with markdown rules