Support custom X-VGI encoding headers for zstd compression and bump version to 0.1.25

Add X-VGI-Accept-Encoding and X-VGI-Content-Encoding custom headers
to bypass proxies/CDNs that strip standard Content-Encoding headers.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: rustyconover

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "vgi-rpc"
-version = "0.1.24"
+version = "0.1.25"
 description = "Vector Gateway Interface - RPC framework based on Apache Arrow"
 readme = "README.md"
 requires-python = ">=3.13"

vgi_rpc/http/_server.py

@@ -1810,9 +1810,11 @@ def __init__(self, level: int) -> None:
 
     def process_request(self, req: falcon.Request, resp: falcon.Response) -> None:
         """Decompress zstd request bodies; record client Accept-Encoding."""
-        # Check if the client accepts zstd responses
+        # Check if the client accepts zstd responses (standard or custom header)
         accept_encoding = req.get_header("Accept-Encoding") or ""
-        req.context.client_accepts_zstd = "zstd" in accept_encoding
+        custom_accept = req.get_header("X-VGI-Accept-Encoding") or ""
+        req.context.client_accepts_zstd = "zstd" in accept_encoding or "zstd" in custom_accept
+        req.context.use_custom_encoding_header = "zstd" in custom_accept
 
         # Decompress request body if Content-Encoding: zstd
         content_encoding = req.get_header("Content-Encoding") or ""
@@ -1852,7 +1854,10 @@ def process_response(
         compressed = _compress_body(body, self._level)
         resp.data = compressed
         resp.stream = None
-        resp.set_header("Content-Encoding", "zstd")
+        if getattr(req.context, "use_custom_encoding_header", False):
+            resp.set_header("X-VGI-Content-Encoding", "zstd")
+        else:
+            resp.set_header("Content-Encoding", "zstd")
 
 
 class _CapabilitiesMiddleware: