Document `libheif` requirement on MacOS

[FrankenApps]

After extracting the application and trying to run it, it initially crashed at startup:

-------------------------------------
Translated Report (Full Report Below)
-------------------------------------

Process:               oculante [70051]
Path:                  /Applications/oculante.app/Contents/MacOS/oculante
Identifier:            com.github.woelper.oculante
Version:               0.8.9 (20210302.215419)
Code Type:             X86-64 (Native)
Parent Process:        launchd [1]
User ID:               501

Date/Time:             2024-02-25 09:12:35.9615 +0100
OS Version:            macOS 14.2.1 (23C71)
Report Version:        12
Bridge OS Version:     8.2 (21P2057)
Anonymous UUID:        98931858-E38B-0B7F-36B5-E4EBC087D966

Sleep/Wake UUID:       79B4198E-AF9E-40AF-A115-7F1F993369AC

Time Awake Since Boot: 860000 seconds
Time Since Wake:       839 seconds

System Integrity Protection: enabled

Crashed Thread:        0

Exception Type:        EXC_CRASH (SIGABRT)
Exception Codes:       0x0000000000000000, 0x0000000000000000

Termination Reason:    Namespace DYLD, Code 1 Library missing
Library not loaded: /usr/local/opt/libheif/lib/libheif.1.dylib
Referenced from: <81BEECF2-DF4E-3C88-B859-EE06CC3B78C5> /Applications/oculante.app/Contents/MacOS/oculante
Reason: tried: '/usr/local/opt/libheif/lib/libheif.1.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/usr/local/opt/libheif/lib/libheif.1.dylib' (no such file), '/usr/local/opt/libheif/lib/libheif.1.dylib' (no such file), '/usr/local/lib/libheif.1.dylib' (no such file), '/usr/lib/libheif.1.dylib' (no such file, not in dyld cache)
(terminated at launch; ignore backtrace)

Thread 0 Crashed:
0   dyld                          	    0x7ff80feb688e __abort_with_payload + 10
1   dyld                          	    0x7ff80fed0d95 abort_with_payload_wrapper_internal + 82
2   dyld                          	    0x7ff80fed0dc7 abort_with_payload + 9
3   dyld                          	    0x7ff80fe5213b dyld4::halt(char const*, dyld4::StructuredError const*) + 335
4   dyld                          	    0x7ff80fe4f525 dyld4::prepare(dyld4::APIs&, dyld3::MachOAnalyzer const*) + 4137
5   dyld                          	    0x7ff80fe4e31f start + 1839


Thread 0 crashed with X86 Thread State (64-bit):
  rax: 0x0000000002000209  rbx: 0x0000000000000001  rcx: 0x00007ff7b9161568  rdx: 0x00007ff7b91619d0
  rdi: 0x0000000000000006  rsi: 0x0000000000000001  rbp: 0x00007ff7b91615b0  rsp: 0x00007ff7b9161568
   r8: 0x00007ff7b91615d0   r9: 0x0000000000000000  r10: 0x0000000000000072  r11: 0x0000000000000246
  r12: 0x0000000000000000  r13: 0x00007ff7b91619d0  r14: 0x0000000000000006  r15: 0x0000000000000072
  rip: 0x00007ff80feb688e  rfl: 0x0000000000000246  cr2: 0x0000000000000000
  
Logical CPU:     0
Error Code:      0x02000209 
Trap Number:     133


Binary Images:
       0x106d9d000 -        0x1087acfff com.github.woelper.oculante (0.8.9) <81beecf2-df4e-3c88-b859-ee06cc3b78c5> /Applications/oculante.app/Contents/MacOS/oculante
    0x7ff80fe48000 -     0x7ff80fee43bf dyld (*) <ab17bf63-259b-3b48-8d70-863166a2191c> /usr/lib/dyld
               0x0 - 0xffffffffffffffff ??? (*) <00000000-0000-0000-0000-000000000000> ???

External Modification Summary:
  Calls made by other processes targeting this process:
    task_for_pid: 0
    thread_create: 0
    thread_set_state: 0
  Calls made by this process:
    task_for_pid: 0
    thread_create: 0
    thread_set_state: 0
  Calls made by all processes on this machine:
    task_for_pid: 0
    thread_create: 0
    thread_set_state: 0

So naturally I installed libheif using homebrew: brew install libheif and now it works fine