feat(starknet): honor HTTP(S)_PROXY env vars in outbound JSON-RPC clients

[kariy]

Adds a reqwest-backed implementation of jsonrpsee's ClientT trait (katana_starknet::http::HttpClient) and makes it the default transport for StarknetRpcClient and the RPC server's PaymasterProxy, so all outbound JSON-RPC connections (forking, full-node sync, messaging, TEE, bootstrap, paymaster forwarding) honor the standard proxy environment variables like the rest of katana's reqwest/alloy clients already do.

Proxy environment variables

HTTPS_PROXY is the de-facto standard way to route a process's outbound traffic through a forward proxy — needed in environments without direct egress, e.g. corporate networks or sandboxed/TEE VMs. Katana now reads:

Variable	Effect
HTTPS_PROXY	Proxy for https:// targets. The client opens an HTTP CONNECT tunnel through the proxy and runs TLS end-to-end inside it, so the proxy never sees plaintext.
HTTP_PROXY	Proxy for plain http:// targets (requests are forwarded in absolute-form).
NO_PROXY	Comma-separated hosts/domains/CIDRs that must connect directly.

Lowercase variants (https_proxy, …) are also recognized. Values are read when a client is constructed, i.e. at node startup. Example:

HTTPS_PROXY=http://proxy.internal:3128 katana --forking.provider https://api.cartridge.gg/x/starknet/mainnet

Loopback bypass: targets on localhost/127.0.0.1/::1 always connect directly, even with a proxy configured — local sidecars (paymaster, VRF) and dev/test flows keep working without users having to maintain a NO_PROXY entry.

Not covered: SOCKS proxies and OS-level proxy settings (macOS System Settings / Windows registry); only the environment variables are read. See docs/proxy.md for the full write-up.

Why a new transport

jsonrpsee's hyper-based HttpClient hardcodes its connector and has no proxy support, so the jsonrpsee-built clients were the only ones in katana that ignored these variables. The new transport mirrors jsonrpsee's wire format, request-id checking, and error-variant semantics, so StarknetApiError mapping and retry classification are unchanged; the WebSocket client and localhost-only helpers stay on jsonrpsee.

Covered by 9 new tests, including proxy routing through a mock forward proxy (asserting absolute-form forwarding) and loopback bypass.

🤖 Generated with Claude Code

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.30.

Benchmark suite	Current: 600f431	Previous: 3d856a6	Ratio
ContractClassChange/compress	183 ns/iter (± 2)	139 ns/iter (± 2)	1.32
GenericContractInfo/decompress	102 ns/iter (± 3)	78 ns/iter (± 2)	1.31
FinalityStatus/compress	1 ns/iter (± 0)	0 ns/iter (± 0)	+∞
VersionedContractClass/compress	377 ns/iter (± 5)	282 ns/iter (± 6)	1.34
TrieHistoryEntry/decompress	260 ns/iter (± 10)	190 ns/iter (± 4)	1.37

This comment was automatically generated by workflow using github-action-benchmark.

CC: @kariy

[github-actions]

Codec benchmark diff vs main

Benchmark	Baseline (ns)	Current (ns)	Δ
CompiledClass(fixture)/compress	2172076	2760487	+27.09%
CompiledClass(fixture)/decompress	2544155	2814941	+10.64%
ExecutionCheckpoint/compress	28	33	+17.86%
ExecutionCheckpoint/decompress	21	24	+14.29%
PruningCheckpoint/compress	28	32	+14.29%
PruningCheckpoint/decompress	21	24	+14.29%
VersionedHeader/compress	574	652	+13.59%
VersionedHeader/decompress	655	825	+25.95%
StoredBlockBodyIndices/compress	64	75	+17.19%
StoredBlockBodyIndices/decompress	34	35	+2.94%
StorageEntry/compress	108	134	+24.07%
StorageEntry/decompress	112	137	+22.32%
ContractNonceChange/compress	108	138	+27.78%
ContractNonceChange/decompress	185	235	+27.03%
ContractClassChange/compress	139	183	+31.65%
ContractClassChange/decompress	196	250	+27.55%
ContractStorageEntry/compress	119	147	+23.53%
ContractStorageEntry/decompress	254	311	+22.44%
GenericContractInfo/compress	106	131	+23.58%
GenericContractInfo/decompress	78	102	+30.77%
Felt/compress	55	68	+23.64%
Felt/decompress	45	51	+13.33%
BlockHash/compress	55	68	+23.64%
BlockHash/decompress	45	51	+13.33%
TxHash/compress	55	68	+23.64%
TxHash/decompress	46	51	+10.87%
ClassHash/compress	55	68	+23.64%
ClassHash/decompress	45	51	+13.33%
CompiledClassHash/compress	55	67	+21.82%
CompiledClassHash/decompress	46	51	+10.87%
BlockNumber/compress	28	30	+7.14%
BlockNumber/decompress	21	24	+14.29%
TxNumber/compress	28	30	+7.14%
TxNumber/decompress	21	24	+14.29%
FinalityStatus/compress	0	1	+Infinity%
FinalityStatus/decompress	8	10	+25.00%
TypedTransactionExecutionInfo/compress	31280	16211	-48.17%
TypedTransactionExecutionInfo/decompress	3195	3567	+11.64%
VersionedContractClass/compress	282	377	+33.69%
VersionedContractClass/decompress	655	772	+17.86%
MigratedCompiledClassHash/compress	109	136	+24.77%
MigratedCompiledClassHash/decompress	110	142	+29.09%
ContractInfoChangeList/compress	1346	1406	+4.46%
ContractInfoChangeList/decompress	1990	2180	+9.55%
BlockChangeList/compress	540	610	+12.96%
BlockChangeList/decompress	798	853	+6.89%
ReceiptEnvelope/compress	26970	27859	+3.30%
ReceiptEnvelope/decompress	5497	5930	+7.88%
TrieDatabaseValue/compress	140	165	+17.86%
TrieDatabaseValue/decompress	250	234	-6.40%
TrieHistoryEntry/compress	266	286	+7.52%
TrieHistoryEntry/decompress	190	260	+36.84%

[github-actions]

Runner: AMD EPYC 7763 64-Core Processor (4 cores) · 15Gi RAM

[codecov]

Codecov Report

❌ Patch coverage is 94.55128% with 17 lines in your changes missing coverage. Please review.
✅ Project coverage is 68.44%. Comparing base (9bde0ae) to head (600f431).
⚠️ Report is 501 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/starknet/src/http.rs	94.49%	17 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #643      +/-   ##
==========================================
- Coverage   73.32%   68.44%   -4.88%     
==========================================
  Files         209      336     +127     
  Lines       23132    47368   +24236     
==========================================
+ Hits        16961    32422   +15461     
- Misses       6171    14946    +8775     

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