Replace local storage allocation search with sort / pair algorithm - #11011

control: job assigned to worker 01M0K3G6ZB9QJVYDXJVR6NDHHR [factory aws, i-04520a8bc79da8525] (queued for 57 s)
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task: starting task 0: "setup"
task: process exited: duration 4113 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 16792 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 21 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 12820 ms, exit code 0
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task: starting task 4: "build"
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|  Documenting omicron-uuid-kinds v0.1.0 (/work/oxidecomputer/omicron/uuid-kinds)
|  Documenting dev-tools-common v0.1.0 (/work/oxidecomputer/omicron/dev-tools/common)
|     Finished `dev` profile [unoptimized + debuginfo] target(s) in 7m 18s
| warning: the following packages contain code that will be rejected by a future version of  [...]
| note: to see what the problems were, use the option `--future-incompat-report`, or run `ca [...]
|    Generated /work/oxidecomputer/omicron/target/doc/api_identity/index.html and 203 other  [...]
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| real     7:18.609524412
| user    20:00.555414333
| sys      4:17.337054533
| trap        0.293352066
| tflt        0.003281050
| dflt        0.042365657
| kflt        0.000025860
| lock  6:57:28.100819547
| slp   2:27:03.403652305
| lat        33.687328581
| stop     2:08.386117610
task: process exited: duration 822266 ms, exit code 0
|W| found 0 output files