Re-pin XDR to stellar-xdr#307 head and split curr/next feature gates

The Makefile pinned 68fa1ac5, which predates the CAP-0084 XDR commit,
and left XDR_FEATURES undefined, so `make generate` could not reproduce
the committed generated codec. Pin XDR_BASE_URL_{CURR,NEXT} to
stellar-xdr@787382ef (CAP-0084 muxed-contract arm) and split into
XDR_FEATURES_CURR=CAP_0083 / XDR_FEATURES_NEXT=CAP_0083,CAP_0084_MUXED_CONTRACT
so curr excludes and next includes the muxed-contract arm, mirroring
stellar/js-stellar-base#981. Drop `docker run -it` for non-TTY/CI regen
and wire the xdrgen#152 const-inlining post-process (scripts/post-process-generated.py)
for curr and next.

Regen deferred: Docker is unavailable in this environment, so
`make generate` was not re-run. The Makefile is now reproducible against
787382ef and the const post-process is wired but not yet executed; the
committed src/base/generated/* (correct CAP-0084 arm content, CI green)
are unchanged.

Author: sisuresh

Makefile

@@ -1,5 +1,12 @@
-XDR_BASE_URL_CURR=https://github.com/stellar/stellar-xdr/raw/68fa1ac55692f68ad2a2ca549d0a283273554439
+# CAP-83 + CAP-84 pre-release: pin to the protocol-28 .x and resolve
+# feature gates via `stellar-xdr xfile preprocess` (rs-stellar-xdr #503) before
+# xdrgen, since the Ruby xdrgen used here does not understand #ifdef.
+# CAP_0084_MUXED_CONTRACT is gated to the `next` channel only: the muxed
+# contract address arm is not enabled on `curr` until protocol 28 ships.
+XDR_BASE_URL_CURR=https://github.com/stellar/stellar-xdr/raw/787382ef2099cca168ca1cb282730d6b7b9e2f16
 XDR_BASE_LOCAL_CURR=xdr/curr
+XDR_FEATURES_CURR=CAP_0083
+XDR_FEATURES_NEXT=CAP_0083,CAP_0084_MUXED_CONTRACT
 XDR_FILES_CURR= \
 	Stellar-SCP.x \
 	Stellar-ledger-entries.x \
@@ -15,7 +22,7 @@ XDR_FILES_CURR= \
 	Stellar-exporter.x
 XDR_FILES_LOCAL_CURR=$(addprefix xdr/curr/,$(XDR_FILES_CURR))
 
-XDR_BASE_URL_NEXT=https://github.com/stellar/stellar-xdr/raw/68fa1ac55692f68ad2a2ca549d0a283273554439
+XDR_BASE_URL_NEXT=https://github.com/stellar/stellar-xdr/raw/787382ef2099cca168ca1cb282730d6b7b9e2f16
 XDR_BASE_LOCAL_NEXT=xdr/next
 XDR_FILES_NEXT= \
 	Stellar-SCP.x \
@@ -43,23 +50,25 @@ generate: src/base/generated/curr_generated.js src/base/generated/curr.d.ts src/
 src/base/generated/curr_generated.js: $(XDR_FILES_LOCAL_CURR)
 	mkdir -p $(dir $@)
 	> $@
-	docker run -it --rm -v $$PWD:/wd -w /wd ruby:3.1 /bin/bash -c '\
+	docker run --rm -v $$PWD:/wd -w /wd ruby:3.1 /bin/bash -c '\
 		gem install specific_install -v 0.3.8 && \
 		gem specific_install https://github.com/stellar/xdrgen.git -b $(XDRGEN_COMMIT) && \
 		xdrgen --language javascript --namespace curr --output src/base/generated $^ \
 		'
+	python3 scripts/post-process-generated.py $@
 
 src/base/generated/next_generated.js: $(XDR_FILES_LOCAL_NEXT)
 	mkdir -p $(dir $@)
 	> $@
-	docker run -it --rm -v $$PWD:/wd -w /wd ruby:3.1 /bin/bash -c '\
+	docker run --rm -v $$PWD:/wd -w /wd ruby:3.1 /bin/bash -c '\
 		gem install specific_install -v 0.3.8 && \
 		gem specific_install https://github.com/stellar/xdrgen.git -b $(XDRGEN_COMMIT) && \
 		xdrgen --language javascript --namespace next --output src/base/generated $^ \
 		'
+	python3 scripts/post-process-generated.py $@
 
 src/base/generated/curr.d.ts: src/base/generated/curr_generated.js
-	docker run -it --rm -v $$PWD:/wd -w / --entrypoint /bin/sh node:22-alpine -c '\
+	docker run --rm -v $$PWD:/wd -w / --entrypoint /bin/sh node:22-alpine -c '\
 		apk add --update git && \
 		corepack enable && \
 		corepack prepare pnpm@$(PNPM_VERSION) --activate && \
@@ -73,7 +82,7 @@ src/base/generated/curr.d.ts: src/base/generated/curr_generated.js
 		'
 
 src/base/generated/next.d.ts: src/base/generated/next_generated.js
-	docker run -it --rm -v $$PWD:/wd -w / --entrypoint /bin/sh node:22-alpine -c '\
+	docker run --rm -v $$PWD:/wd -w / --entrypoint /bin/sh node:22-alpine -c '\
 		apk add --update git && \
 		corepack enable && \
 		corepack prepare pnpm@$(PNPM_VERSION) --activate && \
@@ -92,12 +101,12 @@ clean:
 $(XDR_FILES_LOCAL_CURR):
 	mkdir -p $(dir $@)
 	curl -L -o $@ $(XDR_BASE_URL_CURR)/$(notdir $@)
-	stellar-xdr xfile preprocess --features "$(XDR_FEATURES)" $@ > $@.pp && mv -f $@.pp $@
+	stellar-xdr xfile preprocess --features "$(XDR_FEATURES_CURR)" $@ > $@.pp && mv -f $@.pp $@
 
 $(XDR_FILES_LOCAL_NEXT):
 	mkdir -p $(dir $@)
 	curl -L -o $@ $(XDR_BASE_URL_NEXT)/$(notdir $@)
-	stellar-xdr xfile preprocess --features "$(XDR_FEATURES)" $@ > $@.pp && mv -f $@.pp $@
+	stellar-xdr xfile preprocess --features "$(XDR_FEATURES_NEXT)" $@ > $@.pp && mv -f $@.pp $@
 reset-xdr:
 	rm -f xdr/*/*.x
 	rm -f src/base/generated/*.js

scripts/post-process-generated.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python3
+"""Post-process xdrgen JS output to inline xdr.const values at usage sites.
+
+xdrgen master emits `xdr.const("NAME", N);` to register a constant in the
+xdr namespace, then uses the bare identifier later (`xdr.string(NAME)`).
+But `@stellar/js-xdr`'s TypeBuilder.const() does not put NAME into JS scope,
+so the bare identifier ReferenceErrors at runtime.
+
+Injecting `var NAME = N;` at the IIFE top fixes runtime but gets DCE'd by
+terser in the production browser dist. The robust fix is to inline the
+literal at each usage site so there's no identifier for terser to drop.
+
+The `xdr.const("NAME", N);` declaration itself is left untouched: the NAME
+there is a string literal (preceded by a quote), so the negative lookbehind
+below skips it. Constants only referenced via `xdr.lookup("NAME")` string
+lookups are likewise untouched.
+"""
+import re
+import pathlib
+import sys
+
+
+def inline_consts(path: pathlib.Path) -> int:
+    s = path.read_text()
+    consts = dict(re.findall(
+        r'xdr\.const\("([A-Z][A-Z0-9_]+)",\s*(0x[0-9a-fA-F]+|\d+)\);', s
+    ))
+    n_replaced = 0
+    for name, value in consts.items():
+        # Replace bare identifier (not preceded by quote or word char,
+        # not followed by quote or word char). This skips string literals
+        # like "NAME" and xdr.lookup("NAME"), so the xdr.const(...)
+        # declaration's string name is preserved.
+        new_s, count = re.subn(
+            rf'(?<![\w"\'$]){re.escape(name)}(?![\w"\'$])',
+            value,
+            s,
+        )
+        if count > 0:
+            s = new_s
+            n_replaced += count
+    path.write_text(s)
+    return n_replaced
+
+
+if __name__ == "__main__":
+    files = sys.argv[1:] or [
+        "src/base/generated/curr_generated.js",
+        "src/base/generated/next_generated.js",
+    ]
+    for f in files:
+        p = pathlib.Path(f)
+        n = inline_consts(p)
+        print(f"{f}: inlined {n} bare-identifier const reference(s)")