Support .t3d and .cmp legacy file formats

[arthurvd]

Is your feature request related to a problem? Please describe.
For the external forcings converter (#621) we need to be able to parse/load legacy file formats with extensions .t3d, .cmp

Describe the solution you'd like

.cmp format

• Should load .cmp files into a CmpModel, which contains a list of CmpRecords.
• Since D-Flow FM supports both astronomical components and harmonic components in one and the same .cmp file, it is probably convenient to make the first column in a CmpRecord of type Union[float, AstronomicPeriod], where AstronomicPeriod is a subclass of StrEnum, with the supported components in the long list in the next item.
• File format docs: https://content.oss.deltares.nl/delft3dfm2d3d/D-Flow_FM_User_Manual.pdf#subsection.E.2.1
  Addition: here is the list of valid component names (used in column 1), from https://content.oss.deltares.nl/delft3d4/Delft3D-TIDE_User_Manual.pdf#appendix.B :

'SA'
'SSA'
'MSM'
'MM'
'MSF'
'MS0'
'MF'
'KO0'
'MK0'
'SNU'
'SN'
'MSTM'
'MFM'
'2SM'
'MSQM'
'MQM'
'2SMN'
'2OK1'
'2Q1'
'NJ1'
'SIGMA1'
'MUK1'
'NUJ1'
'Q1'
'NK1'
'RO1'
'NUK1'
'O1'
'TAU1'
'MP1'
'M1B'
'M1C'
'M1A'
'M1'
'NO1'
'CHI1'
'LP1'
'PI1'
'TK1'
'P1'
'SK1'
'S1'
'K1'
'MO1'
'SP1'
'PSI1'
'RP1'
'FI1'
'KP1'
'THETA1'
'LABDAO1'
'J1'
'MQ1'
'2PO1'
'SO1'
'OO1'
'2KO1'
'UPSILON1'
'KQ1'
'2MN2S2'
'3MKS2'
'2NS2'
'3MS2'
'OQ2'
'MNK2'
'EPSILON2'
'MNS2'
'2ML2S2'
'MNUS2'
'MNK2S2'
'2MS2K2'
'O2'
'NLK2'
'2MK2'
'2N2'
'MU2'
'2MS2'
'SNK2'
'NA2'
'N2'
'KQ2'
'NB2'
'NU2'
'3MSN2'
'2KN2S2'
'OP2'
'MSK2'
'GAMMA2'
'ALFA2'
'MPS2'
'MA2'
'M2'
'KO2'
'MSP2'
'MB2'
'DELTA2'
'MKS2'
'M2(KS)2'
'2SN(MK)2'
'LABDA2'
'SNM2'
'2MN2'
'L2'
'L2A'
'L2B'
'2SK2'
'T2'
'S2'
'KP2'
'R2'
'K2'
'MSNU2'
'MSN2'
'ZETA2'
'ETA2'
'KJ2'
'MKN2'
'2KM(SN)2'
'2SM2'
'SKM2'
'2MS2N2'
'2SNU2'
'2SN2'
'SKN2'
'MQ3'
'NO3'
'MO3'
'2MK3'
'2MP3'
'M3'
'NK3'
'SO3'
'MP3'
'MK3'
'SP3'
'2MQ3'
'SK3'
'2SO3'
'K3'
'4MS4'
'2MNS4'
'3MK4'
'MNLK4'
'3MS4'
'MSNK4'
'MN4'
'MNU4'
'2MLS4'
'2MSK4'
'M4'
'2MKS4'
'SN4'
'3MN4'
'2SMK4'
'MS4'
'MK4'
'2SNM4'
'2MSN4'
'SL4'
'S4'
'SK4'
'2SMN4'
'3SM4'
'2SKM4'
'MNO5'
'3MK5'
'3MP5'
'M5'
'MNK5'
'2MP5'
'MSO5'
'3MO5'
'MSK5'
'3KM5'
'2(MN)S6'
'3MNS6'
'4MK6'
'2NM6'
'4MS6'
'2MSNK6'
'2MN6'
'2MNU6'
'3MSK6'
'M6'
'MSN6'
'MNK6'
'4MN6'
'MKNU6'
'2(MS)K6'
'2MS6'
'2MK6'
'2SN6'
'3MSN6'
'MKL6'
'2SM6'
'MSK6'
'S6'
'2MNO7'
'2NMK7'
'M7'
'2MSO7'
'MSKO7'
'2(MN)8'
'3MN8'
'3MNKS8'
'M8'
'2MSN8'
'2MNK8'
'3MS8'
'3MK8'
'2SNM8'
'MSNK8'
'2(MS)8'
'2MSK8'
'3SM8'
'2SMK8'
'S8'
'2(MN)K9'
'3MNK9'
'4MK9'
'3MSK9'
'4MN10'
'M10'
'3MSN10'
'4MS10'
'2(MS)N10'
'2MNSK10'
'3M2S10'
'4MSK11'
'M12'
'4MSN12'
'5MS12'
'3MNKS12'
'4M2S12

.t3D legacy file format

.t3D files contain timeseries with multiple data columns to provide boundary values for multiple vertical layers on a boundary.

• Example file:

LAYER_TYPE=SIGMA
LAYERS=0.0 0.5 0.55 0.75 1
TIME = 0 seconds since 2006-01-01 00:00:00 +00:00
41 36.45455 36 34 31
TIME = 180 seconds since 2006-01-01 00:00:00 +00:00
41.00002 36.45456 36.00002 34.00002 31.00002
[..]

• all keywords are case-insensitive.
• Note: this is the legacy file format. It needs a Pydantic class of its own. It contains the same data, but is not to be confused with class T3D, which is a subpart of .bc files (the new preferred format).

Header:

• valid values for LAYER_TYPE:
  • SIGMA
  • Z
• LAYERS: list of whitespace-separated floats, the number of layers is determined after parsing and string splitting.
• optionally after the LAYERS line can be a line:
  VECTORMAX = <n>
  with n a positive integer, defining the number of vector components. Default (when absent) value is 1 (scalar timeseries for each later). Sometimes a velocity vector is specified using VECTORMAX = 2.
  This ends the header.

Data/body:
Now the data part of the file starts. Each record consists of two lines:

• TIME = [..] where time format is <float> <time unit> since <reference date time>
  • <time unit> is one of: 'seconds', 'minutes', 'hours', 'days'
  • <reference date time> is of ISO 8601 format:
    • YYYY-MM-DD,
    • followed by optional time hh:mm:ss (prefixed by either 'T' or ' '), default '00:00:00'
    • followed by optional time zone hh:mm (prefixed by either 'Z' or '+' or '-')