Add Base64 as explicit dependency to Project.toml

Base64 is required for base64encode function used in telemetry.jl
for encoding PNG files for GitHub API uploads. Even though Base64
is a standard library, it needs to be declared as a dependency.

Fixes ArgumentError: Package LinearSolveAutotune does not have Base64 in its dependencies

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: ChrisRackauckas

lib/LinearSolveAutotune/Project.toml

@@ -6,6 +6,7 @@ version = "0.1.0"
 [deps]
 LinearSolve = "7ed4a6bd-45f5-4d41-b270-4a48e9bafcae"
 BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"
+Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
 CSV = "336ed68f-0bac-5ca0-87d4-7b16caf5d00b"
 DataFrames = "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"
 GitHub = "bc5e4493-9b4d-5f90-b8aa-2b2bcaad7a26"
@@ -31,6 +32,7 @@ Metal = "dde4c033-4e86-420c-a63e-0dd931031962"
 [compat]
 LinearSolve = "3"
 BenchmarkTools = "1"
+Base64 = "1"
 CSV = "0.10"
 DataFrames = "1"
 GitHub = "5"