Metal: Use mtl resource shared to avoid one copy

[EricLBuehler]

No description provided.

[EricLBuehler]

Small optimization. Docs: https://developer.apple.com/documentation/metal/mtlstoragemode/shared

We were using: https://developer.apple.com/documentation/metal/mtlstoragemode/managed

[github-actions]

Code Metrics Report

  ===============================================================================
 Language            Files        Lines         Code     Comments       Blanks
===============================================================================
 C Header                2           35           28            0            7
 Dockerfile              1           41           22           10            9
 Happy                   1          442          369            0           73
 JSON                   12          105          104            0            1
 Python                 53         2274         1949           63          262
 Shell                   1           57           22           18           17
 TOML                   18          583          520            2           61
 YAML                    2           21           19            2            0
-------------------------------------------------------------------------------
 Jupyter Notebooks       4            0            0            0            0
 |- Markdown             2           77           32           31           14
 |- Python               2          196          169            1           26
 (Total)                            273          201           32           40
-------------------------------------------------------------------------------
 Markdown               40         3009            0         2286          723
 |- BASH                 6          101           98            0            3
 |- JSON                 1           12           12            0            0
 |- Python               6          114          102            0           12
 |- Rust                10          361          306            0           55
 |- TOML                 2           75           63            0           12
 (Total)                           3672          581         2286          805
-------------------------------------------------------------------------------
 Rust                  280        84143        75488         1744         6911
 |- Markdown           136         1430           25         1301          104
 (Total)                          85573        75513         3045         7015
===============================================================================
 Total                 415        90710        78521         4125         8064
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