[MicroPerf] Fuse the optimizer inlining copy + type-instantiation passes

[T-Gro]

Inlining a generic function saturated by its type arguments cloned the body twice: copyExpr (clone + fresh vals), then a second full traversal inside MakeApplicationAndBetaReduce to substitute the type arguments. remapExpr already applies a type instantiation at every type position, so the generic-inline site now carries the instantiation via mkInstRemap in the same copy pass — one traversal, one val-clone.

Allocation

Release net11.0, 65,880-LOC project, GC.GetTotalAllocatedBytes(true), 3 runs × 4 iters:

build	MB / compile
base	10,662
this PR	10,105
delta	−557 (−5.2%)

Diff

One hunk in Optimizer.fs (+11 / −4). TypedTreeOps.Remapping.* untouched; no new ValCopyFlag case.

match f2 with
| Expr.TyLambda(_, tyvs, body, _, bodyTy) when tyvs.Length = tyargs.Length ->
    let tpinst = bindTypars tyvs tyargs emptyTyparInst
    let bodyR = remapExpr g CloneAllAndMarkExprValsAsCompilerGenerated (mkInstRemap tpinst) body |> remarkExpr m
    MakeApplicationAndBetaReduce g (bodyR, instType tpinst bodyTy, [], argsR, m)
| _ -> // non-TyLambda: unchanged original path

Verification

check	result
EmittedIL + Optimizations suites (net11.0)	671 pass, 0 regressions (6 pre-existing PrintFunction env failures — identical on base)
Differential batteries (generic inline / match / try / for / while / closures / InlineIfLambda / struct / byref / SRTP / GenericZero), --optimize+ and --optimize- --debug:portable	byte-identical IL + PDB vs base
[<ReflectedDefinition>] assembly	reflected-definitions resource-name tag shifts by the newUnique delta (one clone instead of two); pickled-payload hash unchanged, name is prefix-consumed — cosmetic only

Branch fires ~6.2k times per compile of the workload, so the fused path is exercised (not dead).

[github-actions]

❗ Release notes required

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---

✅ Found changes and release notes in following paths:

Change path	Release notes path	Description
`src/Compiler`	docs/release-notes/.FSharp.Compiler.Service/11.0.100.md

[github-actions]

🔍 Tooling Safety Check — Affects-Compiler-Output
Affects-Compiler-Output: modifies Optimizer.fs and TypedTreeOps.Remapping

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