refactor(server): replace ServerCommand enum and binary mapper with wire types

[hubcio]

Server binary handlers duplicated wire format logic from
iggy_binary_protocol. Replace request decoding (ServerCommand
enum + enum_dispatch + BytesSerializable) with direct WireDecode
dispatch, and response encoding (mapper.rs) with WireEncode on
wire response types. Handlers become standalone async functions.

Fix CreateUserRequest/UpdatePermissionsRequest wire format:
perm_len was written unconditionally but iggy_common only
writes it when has_permissions == 1.

Deleted: command.rs, macros.rs, mapper.rs, handlers/utils.rs,
enum_dispatch dependency.

[codecov]

Codecov Report

❌ Patch coverage is 83.25893% with 225 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.78%. Comparing base (38e392a) to head (35892b4).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
core/server/src/binary/dispatch.rs	85.08%	12 Missing and 42 partials ⚠️
core/server/src/websocket/connection_handler.rs	54.34%	20 Missing and 1 partial ⚠️
...er/src/binary/handlers/system/get_stats_handler.rs	80.70%	9 Missing and 2 partials ⚠️
...rs/consumer_offsets/get_consumer_offset_handler.rs	72.22%	2 Missing and 8 partials ⚠️
core/server/src/quic/listener.rs	59.09%	7 Missing and 2 partials ⚠️
core/server/src/tcp/connection_handler.rs	71.87%	8 Missing and 1 partial ⚠️
...lers/consumer_groups/get_consumer_group_handler.rs	78.37%	1 Missing and 7 partials ⚠️
...ers/consumer_groups/get_consumer_groups_handler.rs	71.42%	2 Missing and 6 partials ⚠️
...consumer_offsets/delete_consumer_offset_handler.rs	65.21%	1 Missing and 7 partials ⚠️
...ccess_tokens/get_personal_access_tokens_handler.rs	65.21%	3 Missing and 5 partials ⚠️
... and 19 more

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #3027      +/-   ##
============================================
- Coverage     72.14%   71.78%   -0.36%     
  Complexity      930      930              
============================================
  Files          1120     1117       -3     
  Lines         93489    93031     -458     
  Branches      70838    70391     -447     
============================================
- Hits          67445    66782     -663     
- Misses        23475    23632     +157     
- Partials       2569     2617      +48     

Components	Coverage Δ
Rust Core	72.42% <83.25%> (-0.46%)	⬇️
Java SDK	62.08% <ø> (ø)
C# SDK	67.43% <ø> (-0.21%)	⬇️
Python SDK	81.43% <ø> (ø)
Node SDK	91.40% <ø> (ø)
Go SDK	38.68% <ø> (ø)

Files with missing lines	Coverage Δ
...inary_protocol/src/requests/system/get_snapshot.rs	100.00% <100.00%> (ø)
..._protocol/src/requests/users/update_permissions.rs	95.91% <100.00%> (-0.99%)	⬇️
...y/handlers/cluster/get_cluster_metadata_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
...s/consumer_groups/create_consumer_group_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
...s/consumer_groups/delete_consumer_group_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
...ers/consumer_groups/join_consumer_group_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
...rs/consumer_groups/leave_consumer_group_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
.../binary/handlers/messages/send_messages_handler.rs	100.00% <100.00%> (ø)
...y/handlers/partitions/create_partitions_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
...y/handlers/partitions/delete_partitions_handler.rs	100.00% <100.00%> (+10.52%)	⬆️
... and 51 more

... and 48 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.