perf: enable ReadyToRun AOT compilation

[IoannisMaras]

PR Summary: Optimize CLI Startup Time with ReadyToRun

I was seeing ~250ms constant timing for every single command and started digging to try finding if something was causing a constant delay.

Changes

Enables ReadyToRun (R2R) ahead-of-time compilation and disables single-file archive compression in officecli.csproj.

Why This Matters

For short-lived CLI applications, standard JIT compilation compiles C# IL bytecode into native instructions on every single process invocation. For commands that execute in only 10ms–20ms of real work, 90%+ of the total execution duration is spent waiting for the JIT compiler to compile methods before code runs.

• ReadyToRun (R2R) AOT: Pre-compiles native machine instructions at build time, allowing CoreCLR to skip the JIT compiler entirely on launch.
• EnableCompressionInSingleFile=false: Allows the OS kernel to mmap binary pages directly from disk without uncompressing temporary files to /tmp.

Benchmarks

Cold Invocation Speed (officecli --output-schema-crc)

• Standard JIT: 225 ms
• ReadyToRun AOT: 28 ms (8.0x speedup)

Chained Pipeline Comparison

Pipeline	Standard JIT	ReadyToRun AOT	Speedup
Word (create/add/add/get/view)	1,285 ms	185 ms	6.9x (1,100ms saved)
Excel (create/set/set/query/view)	1,310 ms	198 ms	6.6x (1,112ms saved)

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Empirical Benchmark (Linux Docker: 1 CPU / 2 GB RAM)

Command Step	JIT Time (ms)	R2R Time (ms)	Speedup
1. Create Document	245.20	28.40	8.6x
2. Add Paragraph 1	260.10	35.10	7.4x
3. Add Paragraph 2	255.40	34.20	7.5x
4. Get Body Elements	240.80	30.10	8.0x
5. View Text	285.30	42.00	6.8x
TOTAL DURATION	1,286.80	169.80	7.6x