[Feat, Fix] (MG_Impl, MG_State, MG_Backend): program interface queries from frontend reflection; Espryt state-shadow reset

Wave 2 of the advertised-extension conformance campaign.

PROGRAM INTERFACE QUERIES (the load-bearing piece). glGetProgramInterfaceiv
and the five glGetProgramResource* entry points were answered by the
BACKENDS - Espryt asked the real driver about SPIRV-Cross-generated ESSL
whose namespace is not the GL one (default-block uniforms live in
MGL_GLOBAL_UBO there), and Magma kept a second, partial reflection that
hardcoded types and diverged from the frontend. Both are now deleted; a new
frontend resource-model layer (ProgramInterface.{h,cpp}) answers every
interface - uniforms, uniform blocks, atomic-counter buffers (recovered
from glslang's synthesized gl_AtomicCounterBlock_<binding> lowering),
buffer variables, shader-storage blocks (classified by TType storage
qualifier since glslang reflects them as uniform blocks), program inputs/
outputs (built-ins' layoutLocationEnd sentinel mapped to -1), and
transform-feedback varyings including the gl_NextBuffer/gl_SkipComponentsN
pseudo-varyings - from the glslang reflection the frontend already trusts
for glGetActiveUniform. Name/index round-tripping, the "[0]" array
spelling, and the GL 4.6 table 7.2 prop/error matrix live in the new layer
only; GetActiveUniform*/GetActiveAttrib* are untouched.

glShaderStorageBlockBinding now takes the interface-layer index (the one
GetProgramResourceIndex returns, with a range check it never had), records
the binding on the program keyed by block NAME - the one coordinate all
three index spaces agree on - and delegates by name across the backend
boundary. Both backends reseed the recorded bindings on their own program
rebuilds, so an unrelated resync can no longer silently revert a rebound
block, and GL_BUFFER_BINDING reports the live binding, not the declared
one. The Espryt delegate applies only to an already-synced twin and can no
longer trigger SyncToBackend from a getter; the sync path's GL query
out-params are initialized and clamped (a load-dependent stack-garbage
Vector size crash caught by the gate, reproduced 3/50 pre-fix, 100/100
post-fix under saturating load).

ESPRYT RENDER-STATE SHADOW RESET (rides along because it shares
DirectGLES.cpp): the render-state shadow is file-static and survives
MobileGL context switches, so GL_FRAMEBUFFER_SRGB (and the whole synced-cap
class) leaked between contexts - the cross-test leakage class the CTS maps
have carried for a week. MakeCurrent now invalidates the shadow like it
already invalidates the program/FBO/buffer caches, and the resync resolves
a never-set scissor box to the current surface instead of pushing the
(0,0,0,0) sentinel verbatim (which scissored everything away - caught by
the retrace gate, bisected to the exact field via a bitmask probe, and
fixed by resolving like the viewport path rather than reverting).

Frontend riders exposed by the layer: glGetUniformLocation resolves
arrays-of-arrays element addressing ("a[2][1]"); transform-feedback capture
accepts element-addressed varying names ("b[1]") and snapshots the request
verbatim for the interface (Magma's decorate pass logs loudly that element
capture is unimplemented there - follow-up).

KNOWN GAPS, documented in code and tests: the 6 subroutines-* cases
(glslang refuses subroutine for SPIR-V; wave 3), the 5 separate-programs-*
cases (glslang's pipe-I/O reflection cannot see a separable non-vertex
stage's own inputs; needs stage-aware output validation first), and
uniform-block-types' per-instance stage masks (not derivable from the
reflection).

Gate: 593/593 unit at default and kill-switch, x10 each, plus the SSB race
case 100/100 under 20-way CPU load; ext caselist Espryt 77.87% -> 80.42%,
Magma 77.58% -> 79.39% (+212 fixed, 0 newly broken); program_interface_query
2/43 -> 31/43 unique on Espryt, 9/43 -> 31/43 on Magma, backends now
byte-identical; KHR-GL45.direct_state_access 370/371 + 371/371 with the 4
sRGB leak victims recovered in cross-test ordering; KHR-GL33 held at
9884/9886; full 39x2 CI retrace with zero wave-attributable failures (the
3 failing newly-added fixtures are bit-identical on the pristine baseline).

MobileGL/MG_Backend/BackendObject.h

@@ -181,15 +181,18 @@ namespace MobileGL {
             void (*GetIntegeri_v)(GLenum target, GLuint index, GLint* data);
             void (*GetInteger64i_v)(GLenum target, GLuint index, GLint64* data);
             void (*GetProgramiv)(GLuint program, GLenum pname, GLint* params);
-            void (*GetProgramInterfaceiv)(GLuint program, GLenum programInterface, GLenum pname, GLint* params);
-            GLuint (*GetProgramResourceIndex)(GLuint program, GLenum programInterface, const GLchar* name);
-            void (*GetProgramResourceName)(GLuint program, GLenum programInterface, GLuint index, GLsizei bufSize,
-                                           GLsizei* length, GLchar* name);
-            void (*GetProgramResourceiv)(GLuint program, GLenum programInterface, GLuint index, GLsizei propCount,
-                                         const GLenum* props, GLsizei bufSize, GLsizei* length, GLint* params);
-            GLint (*GetProgramResourceLocation)(GLuint program, GLenum programInterface, const GLchar* name);
-            GLint (*GetProgramResourceLocationIndex)(GLuint program, GLenum programInterface, const GLchar* name);
-            void (*ShaderStorageBlockBinding)(GLuint program, GLuint storageBlockIndex, GLuint storageBlockBinding);
+            // The GL program interface (glGetProgramInterfaceiv / glGetProgramResource*) is NOT
+            // a backend query: it describes the program the application wrote, in the
+            // application's namespace, which neither backend program is in. It is answered
+            // entirely by MG_Impl/GLImpl/Program/ProgramInterface from the frontend reflection.
+            // Takes the block's GL NAME, not glShaderStorageBlockBinding's index. The index
+            // the application passes is the frontend interface-query enumeration's, and no
+            // backend shares that index space: DirectVulkan enumerates SPIR-V descriptor
+            // bindings and DirectGLES asks a real driver about SPIRV-Cross-generated ESSL.
+            // The name is the one coordinate all three agree on, so the frontend resolves the
+            // index against its own enumeration and each backend maps the name to its own.
+            void (*ShaderStorageBlockBinding)(GLuint program, const GLchar* storageBlockName,
+                                              GLuint storageBlockBinding);
             // GL fence sync objects. All entries are optional (may be null); the
             // frontend then falls back to always-signaled sync semantics.
             // FenceSync may itself return null when the backend cannot create a