refactor: move the syntax module from candid to candid_parser

[ilbertt]

Overview
Effectively reverts #622.

[christoph-dfinity]

LGTM

[github-actions]

Name	Max Mem (Kb)	Encode	Decode
blob	4_224	4_206_641 ($\textcolor{red}{0.00\%}$)	2_121_055 ($\textcolor{red}{0.00\%}$)
btreemap	75_456	4_261_360_790 ($\textcolor{red}{0.00\%}$)	15_191_359_361 ($\textcolor{red}{0.00\%}$)
nns	192	1_975_174 ($\textcolor{red}{0.65\%}$)	5_468_145 ($\textcolor{red}{0.23\%}$)
nns_list_proposal	1_088	6_824_722 ($\textcolor{red}{0.33\%}$)	66_996_590 ($\textcolor{red}{0.33\%}$)
option_list	128	7_481_223 ($\textcolor{red}{0.01\%}$)	25_531_164 ($\textcolor{red}{0.43\%}$)
text	6_336	4_203_506 ($\textcolor{red}{0.00\%}$)	7_877_219 ($\textcolor{red}{0.00\%}$)
variant_list	128	7_537_414 ($\textcolor{red}{0.01\%}$)	24_121_592 ($\textcolor{red}{0.83\%}$)
vec_int16	16_704	123_693_084 ($\textcolor{red}{0.00\%}$)	1_019_238_917 ($\textcolor{red}{0.00\%}$)

• Parser cost: 15_219_400 ($\textcolor{red}{0.01\%}$)
• Extra args: 3_165_449 ($\textcolor{red}{0.63\%}$)

Click to see raw report

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Benchmark: blob
  total:
    instructions: 6.33 M (0.00%) (change within noise threshold)
    heap_increase: 66 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 4.21 M (0.00%) (change within noise threshold)
    heap_increase: 66 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 2.12 M (0.00%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: text
  total:
    instructions: 12.08 M (0.00%) (change within noise threshold)
    heap_increase: 99 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 4.20 M (0.00%) (change within noise threshold)
    heap_increase: 66 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 7.88 M (0.00%) (change within noise threshold)
    heap_increase: 33 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: vec_int16
  total:
    instructions: 1.14 B (0.00%) (change within noise threshold)
    heap_increase: 261 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 123.69 M (0.00%) (change within noise threshold)
    heap_increase: 261 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 1.02 B (0.00%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: btreemap
  total:
    instructions: 19.45 B (0.00%) (change within noise threshold)
    heap_increase: 1179 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 4.26 B (0.00%) (change within noise threshold)
    heap_increase: 159 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 15.19 B (0.00%) (change within noise threshold)
    heap_increase: 1020 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: option_list
  total:
    instructions: 33.01 M (0.33%) (change within noise threshold)
    heap_increase: 2 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 7.48 M (0.01%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 25.53 M (0.43%) (change within noise threshold)
    heap_increase: 2 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: variant_list
  total:
    instructions: 31.66 M (0.63%) (change within noise threshold)
    heap_increase: 2 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 7.54 M (0.01%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 24.12 M (0.83%) (change within noise threshold)
    heap_increase: 2 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: nns
  total:
    instructions: 23.51 M (0.12%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  0. Parsing (scope):
    calls: 1 (no change)
    instructions: 15.22 M (0.01%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 1.98 M (0.65%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 5.47 M (0.23%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: nns_list_proposal
  total:
    instructions: 73.82 M (0.33%) (change within noise threshold)
    heap_increase: 17 pages (no change)
    stable_memory_increase: 0 pages (no change)

  1. Encoding (scope):
    calls: 1 (no change)
    instructions: 6.82 M (0.33%) (change within noise threshold)
    heap_increase: 3 pages (no change)
    stable_memory_increase: 0 pages (no change)

  2. Decoding (scope):
    calls: 1 (no change)
    instructions: 67.00 M (0.33%) (change within noise threshold)
    heap_increase: 14 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Benchmark: extra_args
  total:
    instructions: 3.17 M (0.63%) (change within noise threshold)
    heap_increase: 0 pages (no change)
    stable_memory_increase: 0 pages (no change)

---------------------------------------------------

Summary:
  instructions:
    status:   No significant changes 👍
    counts:   [total 9 | regressed 0 | improved 0 | new 0 | unchanged 9]
    change:   [max +246.06K | p75 +109.13K | median +19.76K | p25 +314 | min +103]
    change %: [max +0.63% | p75 +0.33% | median +0.12% | p25 0.00% | min 0.00%]

  heap_increase:
    status:   No significant changes 👍
    counts:   [total 9 | regressed 0 | improved 0 | new 0 | unchanged 9]
    change:   [max 0 | p75 0 | median 0 | p25 0 | min 0]
    change %: [max 0.00% | p75 0.00% | median 0.00% | p25 0.00% | min 0.00%]

  stable_memory_increase:
    status:   No significant changes 👍
    counts:   [total 9 | regressed 0 | improved 0 | new 0 | unchanged 9]
    change:   [max 0 | p75 0 | median 0 | p25 0 | min 0]
    change %: [max 0.00% | p75 0.00% | median 0.00% | p25 0.00% | min 0.00%]

---------------------------------------------------
Successfully persisted results to canbench_results.yml