Cleanup 20250902

Acceptance of switches as agreed at https://forge.3gpp.org/rep/ivas-codec-pc/ivas-codec/-/wikis/Meetings/Reports/2025-09-02%20Technical%20Matters:

• FIX_1330_JBM_MEMORY - VA: issue 1330: memory savings in the JBM decoder -> accept
• FIX_1370_EXTERNAL_ORIENTATION_CHECK - Nokia: add sanity check for Euler angles for external orientations -> accept
• FIX_1371_EARLY_PART_INIT_FASTCONV - Nokia: fix uninitialized variable in FASTCONV path of binaural reverb init -> accept